Tuesday 31 July 2012

Mexican Wolf

The Mexican Wolf (Canis lupus baileyi) is a subspecies of the Gray Wolf. It is native to North America, where it is the rarest and most genetically distinct subspecies.

 

 

 

 

 

 

 

 

 

 

 

 

Physical features

 

The Mexican Wolf is the smallest Gray Wolf subspecies present in North America. Reaching an overall length no greater than 1.2–1.5 metres (3.9–4.9 ft) and a maximum height of about 80 centimetres (31 in), it is around the size of a German Shepherd. Weight ranges from 27–37 kilograms (60–82 lb). In stature, it resembles some European wolves, though its head is usually broader, its neck thicker, its ears longer and its tail shorter.

History

 

Illustration of a Mexican Wolf
 
The Mexican Wolf was described by both naturalists Hernández and Fernandez.

Former range and extirpation

 

Until recent times, the Mexican Wolf ranged the Sonoran and Chihuahuan Deserts from central Mexico to western Texas, southern New Mexico, and central Arizona. By the turn of the 20th century, reduction of natural prey like deer and elk caused many wolves to begin attacking domestic livestock, which led to intensive efforts by government agencies and individuals to eradicate the Mexican Wolf. Hunters also hunted down the wolf because it killed deer. Trappers and private trappers have also helped in the eradication of the Mexican Wolf. (Note that recent studies completed by genetics experts show evidence of Mexican Wolves ranging as far north as Colorado). These efforts were very successful, and by the 1950s, the Mexican Wolf had been eliminated from the wild. In 1976, the Mexican Wolf was declared an endangered subspecies and has remained so ever since. Today, an estimated 340 Mexican Wolves survive in 49 facilities at the United States and Mexico.

Reintroduction to the Southwest


In 1997, controversy arose when a captive pack at Carlsbad Caverns National Park designated for release was found by Roy McBride, who had captured many wolves for the recovery program in the 1970s, to be largely composed of wolf-dog hybrids. Though staff initially argued that the animals' odd appearance was due to captivity and diet, it was later decided to euthanise them.
In March 1998, the United States Fish and Wildlife Service (USFWS) began reintroducing Mexican Wolves into the Blue Range area of Arizona. The overall objective of this program was to reestablish 100 Mexican Wolves in the Apache and Gila National Forests of Arizona and New Mexico by 2008.
On March 30, 1998, government biologists released 11 gray wolves – 3 adult males, 3 adult females, 3 female pups and yearlings and 2 male pups — from 3 chain-link acclimation pens within the 18,130 square kilometres (7,000 sq mi), federally designated Blue Range Wolf Recovery Area in east-central Arizona.
A population count completed by the Interagency Field Team (IFT) in the winter of 2006–2007 estimated 60 wolves living in the recovery area in several packs. The population goal for 2006 was 100 wolves. In early 2011 there were only two breeding pairs and the population count was 50, up from 42 in the early 2010 count. As of February 2012, the number of breeding pairs rose to six with a total population count of 58, including 32 wolves in six packs on the Arizona side of the recovery area and 26 wolves in six packs on the New Mexico side. There were 18 pups born in 2011 that survived through Dec. 31, 2011. Nine wolves died in 2011, two were shot illegally. 
In February 2010, three captive Mexican Wolves living in the Wildlife Science Center in Forest Lake, Minnesota, escaped from their pen after it was pried open by unknown individuals. Two of the wolves came back on their own the next day; the third wolf, the alpha of the pack, had to be chased down in suburban areas until captured.

Captive breeding programs

 

There are 47 Mexican Wolf breeding facilities in United States and Mexico with the largest in the world being the Wild Canid Survival and Research Center near Eureka, Missouri, which was founded in 1971 by naturalist Marlin Perkins. Another captive breeding center that was founded in 1977 is the California Wolf Center located in Julian, California. The Center is the third largest breeding and host facility for Mexican gray wolves in the United States.

Monday 30 July 2012

Leatherback Sea Turtle

Dermochelys coriacea (beach).jpgThe leatherback sea turtle (Dermochelys coriacea), sometimes called the lute turtle, is the largest of all living sea turtles and the fourth largest modern reptile behind three crocodilians. It is the only living species in the genus Dermochelys. It can easily be differentiated from other modern sea turtles by its lack of a bony shell. Instead, its carapace is covered by skin and oily flesh. Dermochelys coriacea is the only extant member of the family Dermochelyidae.

 

Anatomy and physiology

 

Leatherback turtles have the most hydrodynamic body design of any sea turtle, with a large, teardrop-shaped body. A large pair of front flippers power the turtles through the water. Like other sea turtles, the leatherback has flattened forelimbs adapted for swimming in the open ocean. Claws are absent from both pairs of flippers. The leatherback's flippers are the largest in proportion to its body among extant sea turtles. Leatherback's front flippers can grow up to 2.7 metres (8.9 ft) in large specimens, the largest flippers (even in comparison to its body) of any sea turtle.

A leatherback turtle covering her eggs, Turtle Beach, Tobago.ogv
A leatherback turtle covering her eggs, Turtle Beach, Tobago
 
The leatherback has several characteristics that distinguish it from other sea turtles. Its most notable feature is the lack of a bony carapace. Instead of scutes, it has thick, leathery skin with embedded minuscule osteoderms. Seven distinct ridges rise from the carapace, crossing from the anterior to posterior margin of the turtle's back. Leatherbacks are unique among reptiles in that their scales lack β-keratin. The entire turtle's dorsal surface is colored dark grey to black, with a scattering of white blotches and spots. Demonstrating countershading, the turtle's underside is lightly colored.
Instead of teeth, the leatherback turtle has points on the tomium of its upper lip, with backwards spines in its throat to help it swallow food.
Dermochelys coriacea adults average 1–1.75 metres (3.3–5.74 ft) in carapace length, 1.83–2.2 metres (6.0–7.2 ft) in total length and weigh 250 to 700 kilograms (550 to 1,500 lb). The largest ever found, however, was over 3 metres (9.8 ft) from head to tail, including a carapace length of over 2.2 metres (7.2 ft), and weighed 916 kilograms (2,020 lb). That specimen was found on a beach on the west coast of Wales.
Dermochelys coriacea exhibits a suite of anatomical characteristics believed to be associated with a life in cold waters, including an extensive covering of brown adipose tissue, temperature independent swimming muscles, counter-current heat exchangers between the large front flippers and the core body, as well as an extensive network of counter-current heat exchangers surrounding the trachea.

Physiology

 

Leatherbacks have been viewed as unique among reptiles for their ability to maintain high body temperatures using metabolically generated heat, or endothermy. Initial studies on leatherback metabolic rates found leatherbacks had resting metabolisms around three times higher than expected for a reptile of their size. However, recent studies using reptile representatives encompassing all the size ranges leatherbacks pass through during ontogeny discovered the resting metabolic rate of a large Dermochelys coriacea is not significantly different from predicted results based on allometry.
Rather than use a high resting metabolism, leatherbacks appear to take advantages of a high activity rate. Studies on wild D.coriacea discovered individuals may spend as little as 0.1% of the day resting. This constant swimming creates muscle-derived heat. Coupled with their counter-current heat exchangers, insulating fat covering and large size, leatherbacks are able to maintain high temperature differentials compared to the surrounding water. Adult leatherbacks have been found with core body temperatures that were 18 °C (32.4 °F) above the water they were swimming in.
Leatherback turtles are one of the deepest diving marine animals. Individuals have been recorded diving to depths as great as 1,280 metres (4,200 ft). Typical dive durations are between 3 and 8 minutes, with dives of 30–70 minutes occurring infrequently.
They are also the fastest-moving reptiles. The 1992 edition of the Guinness Book of World Records lists the leatherback turtle moving at 35.28 kilometres per hour (21.92 mph) in the water. More typically, they swim at 0.5–2.8 metres per second (1.1–6.3 mph).

Distribution

 

The leatherback turtle is a species with a cosmopolitan global range. Of all the extant sea turtle species, D. coriacea has the widest distribution, reaching as far north as Alaska and Norway and as far south as the Cape of Good Hope in Africa and the southernmost tip of New Zealand. The leatherback is found in all tropical and subtropical oceans, and its range extends well into the Arctic Circle.
There are three major, genetically distinct populations. The Atlantic Dermochelys population is separate from the ones in the eastern and western Pacific, which are also distinct from each other.
While nesting beaches have been identified in the region, leatherback populations in the Indian Ocean remain generally unassessed and unevaluated.
D. coriacea distribution - yellow circles represent minor nesting locations, red 
circles are known major nesting sites.
 
Recent estimates of global nesting populations are that 26,000 to 43,000 females nest annually, which is a dramatic decline from the 115,000 estimated in 1980. These declining numbers have energized efforts to rebuild the species, which currently is critically endangered.

Atlantic subpopulation

 

The leatherback turtle population in the Atlantic Ocean ranges across the entire region. They range as far north as the North Sea and to the Cape of Good Hope in the south. Unlike other sea turtles, leatherback feeding areas are in colder waters, where there is an abundance of their jellyfish prey, which broadens their range. However, only a few beaches on both sides of the Atlantic provide nesting sites.
Off the Atlantic coast of Canada, leatherback turtles feed in the Gulf of Saint Lawrence near Quebec and as far north as Newfoundland and Labrador. The most significant Atlantic nesting sites are in Suriname, French Guiana and Trinidad and Tobago in the Caribbean and Gabon in Central Africa. The beaches of Mayumba National Park in Mayumba, Gabon host the largest nesting population on the African continent and possibly worldwide, with nearly 30,000 turtles visiting its beaches each year in April. Off the northeastern coast of the South American continent, a few select beaches between French Guiana and Suriname are primary nesting sites of several species of sea turtles, the majority being leatherbacks. A few hundred nest annually on the eastern coast of Florida. In Costa Rica, the beaches of Gandoca and Parismina provide nesting grounds.

Pacific subpopulation

 

Pacific leatherbacks divide into two populations. One population nests on beaches in Papua, Indonesia and the Solomon Islands and forage across the Pacific in the Northern Hemisphere, along the coasts of California, Oregon, and Washington in North America. The eastern Pacific population forages in the Southern Hemisphere, in waters along the western coast of South America, nesting in Mexico, El Salvador and Costa Rica.
The continental United States offers two major leatherback feeding areas. One well-studied area is just off the northwestern coast near the mouth of the Columbia River. The other American area is located in the state of California. Further north, off the Pacific coast of Canada, leatherbacks visit the beaches of British Columbia.

South China Sea subpopulation

 

A third possible Pacific subpopulation has been proposed, those that nest in Malaysia. This subpopulation, however, has effectively been eradicated. The beach of Rantau Abang in Terengganu, Malaysia, once had the largest nesting population in the world, hosting 10,000 nests per year. The major cause for the decline was egg consumption by humans. Conservation efforts initiated in the 1960s were ineffective because they involved excavating and incubating eggs at artificial sites which inadvertently exposed the eggs to high temperatures. It only became known in the 1980s that sea turtles undergo temperature-dependent sex determination; it is suspected that nearly all the artificially-incubated hatchlings were female. In 2008, two turtles nested at Rantau Abang, and unfortunately the eggs were infertile.

Indian Ocean subpopulation

 

While little research has been done on Dermochelys populations in the Indian Ocean, nesting populations are known from Sri Lanka and the Nicobar Islands. These turtles are proposed to form a separate, genetically distinct Indian Ocean subpopulation.

Ecology and life history

 

Ponteluth.jpg
Eggs

 

Habitat

 

Leatherback turtles can be found primarily in the open ocean. Scientists tracked a leatherback turtle that swam from Indonesia to the U.S. in an epic 20,000 km (12,000 mi) foraging journey over a period of 647 days. Leatherbacks follow their jellyfish prey throughout the day, resulting in turtles "preferring" deeper water in the daytime, and shallower water at night (when the jellyfish rise up the water column). This hunting strategy often places turtles in very frigid waters. One individual was found actively hunting in waters that had a surface temperature of 0.4 °C (32.7 °F).
Its favored breeding beaches are mainland sites facing deep water and they seem to avoid those sites protected by coral reefs.

Feeding

 

Adult D. coriacea turtles subsist almost entirely on jellyfish. Due to their obligate feeding nature, leatherback turtles help control jellyfish populations. Leatherbacks also feed on other soft-bodied organisms, such as tunicates and cephalopods.
Pacific leatherbacks migrate about 6,000 miles (9,700 km) across the Pacific from their nesting sites in Indonesia to eat California jellyfish. One cause for their endangered state is plastic bags floating in the ocean. Pacific leatherback sea turtles mistake these plastic bags for jellyfish; an estimated one third of adult leatherbacks have ingested plastic. Plastic enters the oceans along the west coast of urban areas, where leatherbacks forage; with Californians using upwards of 19 billion plastic bags every year. Several species of sea turtles commonly ingest plastic marine debris, and even small quantities of debris can kill sea turtles by obstructing their digestive tracts. Nutrient dilution, which occurs when plastics displace food in the gut, affects the nutrient gain and consequently the growth of sea turtles. Ingestion of marine debris and slowed nutrient gain leads to increased time for sexual maturation that may affect future reproductive behaviors. These turtles have the highest risk of encountering and ingesting plastic bags offshore of San Francisco Bay, the Columbia River mouth, and Puget Sound.

Lifespan

 

Very little is known of the species' lifespan. Some reports claim "30 years or more" while others state "50 years or more".

Death and decomposition

 

Dead leatherbacks that wash ashore are micro-ecosystems while decomposing. In 1996, a drowned carcass held sarcophagid and calliphorid flies after being picked open by a pair of Coragyps atratus vultures. Infestation by carrion-eating beetles of the families Scarabaeidae, Carabidae, and Tenebrionidae soon followed. After days of decomposition, beetles from the families Histeridae and Staphylinidae and anthomyiid flies invaded the corpse as well. Organisms from more than a dozen families took part in consuming the carcass.

Life history

 

Photo of two a person's hands holding a small sand-covered grey/green turtle
Baby leatherback turtle at Gumbo Limbo Environmental Complex in Boca Raton, Florida
 
Like all sea turtles, leatherbacks start as hatchlings, climbing out of the sands of their nesting beaches. Birds, crustaceans, various carnivorous mammals, other reptiles, and people prey on hatchlings before they reach the water. Once in the water, several varieties of fish will also readily predate the small hatchlings. About 90% of the hatchlings die from predation. Once in the ocean, they are rarely seen before maturity. Dermochelys juveniles spend more of their time in tropical waters than do adults. Once they attain maturity few predators threaten the leatherback, although tiger sharks and killer whales are potential predators.
Adults are prone to long-distance migration. Migration occurs between the cold waters where mature leatherbacks feed, to the tropical and subtropical beaches in the regions where they hatch. In the Atlantic, females tagged in French Guiana have been recaptured on the other side of the ocean in Morocco and Spain.
Mating takes place at sea. Males never leave the water once they enter it, unlike females which nest on land. After encountering a female (who possibly exudes a pheromone to signal her reproductive status), the male uses head movements, nuzzling, biting, or flipper movements to determine her receptiveness. Females mate every two to three years. However, leatherbacks can breed annually. Fertilization is internal, and multiple males usually mate with a single female. This polyandry does not provide the offspring with any special advantages.
While other sea turtle species almost always return to their hatching beach, leatherbacks may choose another beach within the region. They choose beaches with soft sand because their softer shells and plastrons are easily damaged by hard rocks. Nesting beaches also have shallower approach angles from the sea. This is a vulnerability for the turtles because such beaches easily erode.
Females excavate a nest above the high-tide line with their flippers. One female may lay as many as nine clutches in one breeding season. About nine days pass between nesting events. Average clutch size is around 110 eggs, 85% of which are viable. After laying, the female carefully back-fills the nest, disguising it from predators with a scattering of sand.
Cleavage of the cell begins within hours of fertilization, but development is suspended during the gastrulation period of movements and infoldings of embryonic cells, while the eggs are being laid. Development then resumes, but embryos remain extremely susceptible to movement-induced mortality until the membranes fully develop after incubating for 20 to 25 days. The structural differentiation of body and organs (organogenesis) soon follows. The eggs hatch in about sixty to seventy days. As with other reptiles, the nest's ambient temperature determines the sex of the hatchings. After nightfall, the hatchings dig to the surface and walk to the sea.
Leatherback nesting seasons vary by location; it occurs from February to July in Parismina, Costa Rica. Farther east in French Guiana, nesting is from March to August. Atlantic leatherbacks nest between February and July from South Carolina in the United States to the United States Virgin Islands in the Caribbean and to Suriname and Guyana. 
 

Taxonomy and evolution

 

Taxonomy

 

Dermochelys coriacea is the only species in genus Dermochelys. The genus, in turn, contains the only extant member of the family Dermochelyidae.
Domenico Agostino Vandelli named the species first in 1761 as Testudo coriacea after an animal captured at Ostia and donated to the University of Padua by Pope Clement XIII. In 1816, French zoologist Henri Blainville coined the term Dermochelys. The leatherback was then reclassified as Dermochelys coriacea. In 1843, the zoologist Leopold Fitzinger put the genus in its own family, Dermochelyidae. In 1884, the American naturalist Samuel Garman described the species as Sphargis coriacea schlegelii. The two were then united in D. coriacea, with each given subspecies status as D. coriacea coriacea and D. coriacea schlegelii. The subspecies were later labeled invalid synonyms of D. coriacea.
The turtle's common name comes from the leathery texture and appearance of its carapace. Older names include "leathery turtle" and "trunk turtle".

Evolution

 

Leatherback turtles have existed in some form since the first true sea turtles evolved over 110 million years ago during the Cretaceous period. The dermochelyids are close relatives of the family Cheloniidae, which contains the other six extant sea turtle species. However, their sister taxon is the extinct family Protostegidae which included other species not having a hard carapace.

Importance to humans

 

People around the world still harvest sea turtle eggs. Asian exploitation of turtle nests has been cited as the most significant factor for the species' global population decline. In Southeast Asia, egg harvesting in countries such as Thailand and Malaysia has led to a near-total collapse of local nesting populations. In Malaysia, where the turtle is practically locally extinct, the eggs are considered a delicacy. In the Caribbean, some cultures consider the eggs to be aphrodisiacs. They are also a major jellyfish predator which helps keep jellyfish populations in check.

Conservation

 

Adult leatherback turtles have few natural predators once they mature; they are most vulnerable to predation in their early life stages. Birds, small mammals, and other opportunists dig up the nests of turtles and consume eggs. Shorebirds and crustaceans prey on the hatchings scrambling for the sea. Once they enter the water, they become prey to predatory fish and cephalopods. Very few survive to adulthood.
Leatherbacks have slightly fewer human-related threats than other sea turtle species. Their flesh contains too much oil and fat, reducing the demand. However, human activity still endangers leatherback turtles in direct and indirect ways. Directly, a few are caught for their meat by subsistence fisheries. Nests are raided by humans in places such as Southeast Asia.
Many human activities indirectly harm Dermochelys populations. As a pelagic species, D. coriacea is occasionally caught as bycatch. As the largest living sea turtles, turtle excluder devices can be ineffective with mature adults. A reported average of 1,500 mature females were accidentally caught annually in the 1990s. Pollution, both chemical and physical, can also be fatal. Many turtles die from malabsorption and intestinal blockage following the ingestion of balloons and plastic bags which resemble their jellyfish prey. Chemical pollution also has an adverse effect on Dermochelys. A high level of phthalates has been measured in their eggs' yolks.

Global initiatives

 

D. coriacea is listed on Appendix I of CITES, which makes export/import of this species (including parts) illegal.
Conserving Pacific and Eastern Atlantic populations was included among the top ten issues in turtle conservation in the first State of the World's Sea Turtles report published in 2006. The report noted significant declines in the Mexican, Costa Rican and Malaysian populations. The eastern Atlantic nesting population was threatened by increased fishing pressures from eastern South American countries.
The Leatherback Trust was founded specifically to conserve sea turtles, specifically its namesake. The foundation established a sanctuary in Costa Rica, the Parque Marino Las Baulas.

National and local initiatives

 

The leatherback sea turtle is subject to differing conservation laws in various countries.
The United States listed it as an endangered species on 2 June 1970. The passing of the Endangered Species Act three years later ratified its status. In 2012 the National Oceanic and Atmospheric Administration designated 41,914 square miles of Pacific Ocean along California, Oregon and Washington as "critical habitat." In Canada, the Species At Risk Act made it illegal to exploit the species in Canadian waters. The Committee on the Status of Endangered Wildlife in Canada classified it as endangered. Ireland and Wales initiated a joint leatherback conservation effort between Swansea University and University College Cork. Funded by the European Regional Development Fund, the Irish Sea Leatherback Turtle Project focuses on research such as tagging and satellite tracking of individuals.
Earthwatch Institute, a global non-profit that teams volunteers with scientists to conduct important environmental research, launched a program called "Trinidad's Leatherback Sea Turtles." This program strives to help save the world's largest turtle from extinction in Matura Beach, Trinidad, as volunteers work side-by-side with leading scientists and a local conservation group, Nature Seekers. This tropical island off the coast of Venezuela is known for its vibrant ethnic diversity and rich cultural events. It is also the site of one of the most important nesting beaches for endangered leatherback turtles, enormous reptiles that can weigh a ton and dive deeper than many whales. Each year, more than 2,000 female leatherbacks haul themselves onto Matura Beach to lay their eggs. With leatherback populations declining more quickly than any other large animal in modern history, each turtle is precious. On this research project, Dr. Dennis Sammy of Nature Seekers and Dr. Scott Eckert of Wider Caribbean Sea Turtle Conservation Network work alongside a team of volunteers to help prevent extinction of Leatherback Sea Turtles.
Several Caribbean countries started conservation programs, such as The St. Kitts Sea Turtle Monitoring Network, focused on using ecotourism to highlight the leatherback's plight. On the Atlantic coast of Costa Rica, the village of Parismina has one such initiative. Parismina is an isolated sandbar where a large number of leatherbacks lay eggs, but poachers abound. Since 1998, the village has been assisting turtles with a hatchery program. The Parismina Social Club is a charitable organization backed by American tourists and expatriates, which collects donations to fund beach patrols.Mayumba National Park in Gabon, Central Africa was created to protect Africa's most important nesting beach. More than 30,000 turtles nest on Mayumba's beaches between September and April each year.
In mid-2007, the Malaysian Fisheries Department revealed a plan to clone leatherback turtles to replenish the country's rapidly declining population. Some conservation biologists, however, are skeptical of the proposed plan because cloning has only succeeded on mammals such as dogs, sheep, cats, and cattle, and uncertainties persist about cloned animals' health and life spans. Leatherbacks used to nest in the thousands on Malaysian beaches, including those at Terengganu, where more than 3,000 females nested in the late 1960s. The last official count of nesting leatherback females on that beach was recorded to be a mere two females in 1993.
In Brazil, reproduction of the leatherback turtle is being assisted by the IBAMA's "projeto TAMAR" (TAMAR project), which works to protect nests and prevent accidental kills by fishing boats. The last official count of nesting leatherback females in Brazil yielded only seven females. In January 2010, one female at Pontal do Paraná laid hundreds of eggs. Since Leatherback sea turtles had been reported to nest only at Espirito Santo's shore, but never in the state of Paraná, this unusual act brought much attention to the area, biologists have been protecting the nests and checking their eggs' temperature, although it might be that none of the eggs are fertile.
Australia's Environment Protection and Biodiversity Conservation Act 1999, lists D. coriacea as Vulnerable, while Queensland's Nature Conservation Act 1992 lists it as Endangered.

Sunday 29 July 2012

Mediterranian Monk Seal

The Mediterranean monk seal (Monachus monachus) is a pinniped belonging to the Phocidae family. At some 450–510 (fewer than 600) remaining individuals, it is believed to be the world's second-rarest pinniped (second only to the Saimaa ringed seal), and one of the most endangered mammals in the world.
It is present in parts of the Mediterranean Sea and the eastern Atlantic Ocean waters around the Tropic of Cancer, as well.


 

 

 

 

Description

 

This species of monk seal grows from approximately 80 cm long at birth up to an average of 2.4 m (7.95 ft) as adults. Males weigh an average of 315 kg (695 lbs) and females weigh 300 kg (660 lbs)), overall weigh ranging from 240 to 400 kg (530–880 lbs). They are thought to live up to 45 years old; the average life span is thought to be 20 to 25 years old and reproductive maturity is reached at around age four.
The monk seals' pups are about a meter long and weigh around 15–18 kilograms, their skin being covered by 1–1.5 centimeter-long, dark brown to black hair. On their bellies, there is a white stripe, which differs in color between the two sexes. This hair is replaced after six to eight weeks by the usual short hair adults carry.
Pregnant Mediterranean monk seals typically use inaccessible undersea caves while giving birth, though historical descriptions show they used open beaches until the 18th century. There are eight pairs of teeth in both jaws. Believed to have the shortest hair of any pinniped, the Mediterranean monk seal fur is black (males) or brown to dark grey (females), with a paler belly, which is close to white in males. The snout is short broad and flat, with very pronounced, long nostrils that face upward, unlike their Hawaiian relative, which tend to have more forward nostrils. The flippers are relatively short, with small slender claws. Monk seals have two pairs of retractable abdominal teats, unlike most other pinnipeds.

Reproduction

 

Very little is known of this seal's reproduction. Scientists have suggested they are polygynous, with males being very territorial where they mate with females. Although there is no breeding season, since births take place year round, there is a peak in October and November. This is also the time when caves are prone to wash out due to high surf or storm surge, which causes high mortality rates among monk seal pups, especially at the key Cabo Blanco colony. According to the IUCN species factsheet, "pup survival is low; just under 50% survive their first two months to the onset of their moult, and most mortalities occurred in the first two weeks. Survival of pups born from September to January is 29%. This very low survival rate is associated with mortality caused by severe storms, and high swells and tides, but impoverished genetic variability and inbreeding may also be involved. Pups born during the rest of the year had a survival rate of 71%".
In 2008, lactation was reported in an open beach, the first such record since 1945, which could suggest the seal could begin feeling increasingly safe to return to open beaches for breeding purposes in Cabo Blanco.
Pups make first contact with the water two weeks after their birth, and are weaned at around 18 weeks of age; females caring for pups will go off to feed for an average of nine hours. Most individuals are believed to reach maturity at four years of age. The gestation period lasts close to a year. However, it is believed to be common among monk seals of the Cabo Blanco colony to have a gestation period lasting slightly longer than a year.

Diet

 

Mediterranean monk seals are diurnal and feed on a variety of fish and mollusks, primarily octopus, squid, and eels, up to 3 kg per day. They are known to forage mostly at depths of 150–230 feet, but (as a species) have been observed by the NOAA in a submersible at a known feeding ground at a depth of 500m. Monk seals prefer hunting in wide-open spaces, enabling them to use their speed more effectively. They are successful bottom-feeding hunters, and have been observed (as a species) lifting slabs of rock in search of prey.

Habitat

 

The habitat of this pinniped has changed over the years. In ancient times, and up until the 20th century, Mediterranean monk seals had been known to congregate, give birth, and seek refuge on open beaches. In more recent times, they have left their former habitat and now only use sea caves for such things; and more often than not, these caves are rather inaccessible to humans due to underwater entries, and because the caves are often positioned along remote or rugged coastlines.
Scientists have confirmed this is a recent adaptation, most likely due to the rapid increase in human population, tourism, and industry, which have caused the destruction of animals' habitat. Because of these seals' shy nature and sensitivity to human disturbance, they have slowly adapted to try to avoid contact with humans completely within the last century, and, perhaps, even earlier. The coastal caves are, however, dangerous for newborns, and are causes of major mortality among pups.

Status

 

This earless seal's former range extended throughout the Northwest Atlantic Africa, Mediterranean and Black Sea, coastlines, including all offshore islands of the Mediterranean, and into the Atlantic and its islands: Canary, Madeira, Ilhas desertas, Porto Santo... as far west as the Azores. Vagrants could be found as far south as Gambia and the Cape Verde islands, and as far north as continental Portugal and Atlantic France.
Several causes have provoked a dramatic population decrease over time: on one hand, commercial hunting (especially during the Roman Empire and Middle Ages) and, during the 20th century, eradication by fishermen, who used to consider it a pest due to the damage the seal causes to fishing nets when it preys on fish caught in them; and, on the other hand, coastal urbanization and pollution.
The species has gone extinct in the Sea of Marmara due to pollution and heavy ship traffic from the Dardanelles and the Bosporus. In addition, the last report of a seal in the Black Sea dates to the late 1990s.
Nowadays, its entire population is estimated to be less than 600 individuals scattered throughout a wide distribution range, which qualifies this species as Critically Endangered. Its current very sparse population is one more serious threat to the species, as it only has two key sites which can be deemed viable. One is the Aegean Sea (250–300 in Greece and some 100 in Turkey) and the other is the Western Saharan portion of Cabo Blanco (some 130 individuals which may support the small, but growing, nucleus in the Desertas Islands –approximately 20 individuals).
These two key sites are virtually in the extreme opposites of the species' distribution range, which makes natural population interchange between these two key sites impossible. All the other remaining subpopulations are composed of less than 50 mature individuals, many of them being only loose groups of extremely reduced size – often less than 5 individuals.
These other remaining populations are in Madeira, with 30 to 35 individuals, and the Desertas Islands (both in the Atlantic Ocean) and southwestern Turkey and the Ionian Sea (both in the eastern Mediterranean). The species status is virtually moribund in the western Mediterranean, which still holds tiny Moroccan and Algerian populations, associated with rare sightings of vagrants in the Balearic Islands, Sardinia, and other western Mediterranean locations.

Cabo Blanco 1997 die off

 

Cabo Blanco, in the Atlantic Ocean, is the largest surviving single population of the species, and the only remaining site which still seems to preserve a colony structure. In the summer of 1997, two-thirds of its seal population were wiped out within two months, extremely compromising the species' viable population. While opinions on the precise causes of this epidemic remain divided (the most likely cause being a morbilivirus or, more likely, a toxic algae bloom,) the mass die-off emphasized the precarious status of a species already regarded as critically endangered throughout its range.
While still far below the early 1997 count, numbers in this all-important location have started a slow-paced recovery ever since. Currently, the population in this location is estimated at 150 individuals, down from some 310 in 1997, but still the largest single colony by far. The threat of a similar incident that could wipe out the entire population remains.


Preservation

 

Damage inflicted upon fishermen's nets and rare attacks on off-shore fish farms in Turkey and Greece are known to have pushed local people towards hunting the Mediterranean monk seal, but mostly out of revenge, rather than population control. Preservation efforts have been put forth by civic organizations, foundations, and universities in both countries since as early as the 1970s. For the past 10 years, many groups have carried out missions to educate locals on damage control and species preservation. Reports of positive results of such efforts exist throughout the area.
In the Aegean Sea, only Greece has allocated a large area for the preservation of the Mediterranean monk seal and its habitat. The Greek Alonissos Marine Park, that extends around the Northern Sporades islands, is the main action ground of the Greek MOm organisation. MOm is greatly involved in raising awareness in the general public, fundraising for the helping of the monk seal preservation cause, in Greece and wherever needed. Greece is currently investigating the possibility of declaring another monk seal breeding site as a national park, and also has integrated some sites in the NATURA 2000 protection scheme. The legislation in Greece is very strict towards seal hunting, and in general, the public is very much aware and supportive of the effort for the preservation of the Mediterranean monk seal.
The complex politics concerning the covert opposition of the Greek government towards the protection to the monk seals in the eastern Aegean in the late 1970s is described in a book by William Johnson. Oil companies apparently may have been using the Monk Seal Sanctuary project as a stalking horse to encourage greater cooperation between the Greek and Turkish governments as a preliminary to pushing for oil extraction rights in a geopolitically unstable area. According to Johnson, the Greek secret service, the YPEA, were against such moves and sabotaged the project to the detriment both of the seals and conservationists, who, unaware of such covert motivations, sought only to protect the species and its habitat.
One of the largest groups among the foundations concentrating their efforts towards the preservation of the Mediterranean monk seal is the Mediterranean Seal Research Group (Turkish: Akdeniz Foklarını Araştırma Grubu) operating under the Underwater Research Foundation (Turkish: Sualtı Araştırmaları Derneği) in Turkey (also known as SAD-AFAG). The group has taken initiative in joint preservation efforts together with the Foça municipal officials, as well as phone, fax, and email hotlines for sightings.
Preservation of the species requires both the preservation of land and sea, due to the need for terrestrial haul-out sites and caves or caverns for the animal to rest and reproduce. Even though responsible scuba diving instructors hesitate to make trips to known seal caves, the rumor of a seal sighting quickly becomes a tourist attraction for many. Irresponsible scuba diving trips scare the seals away from caves which could become habitation for the species.

Rare Sightings

 

In June 2009, there was a report of a sighting off the island of Giglio, in Italy. On 7 January 2010, fishermen spotted an injured Mediterranean monk seal off the coasts of Tel Aviv, Israel. When zoo veterinarians arrived to help the seal, it had slipped back into the waters. Members of the Israel Marine Mammal Research and Assistance Center arrived at the scene and tried to locate the injured mammal, but with no success. This was the first sighting of the species in the region since Lebanese authorities claimed to have found a population of 10–20 other seals on their coasts 70 years earlier. In addition, the seal was also sighted a couple of weeks later in the northern kibbutz of Rosh Hanikra.
In April 2010, there was a report of a sighting off the island of Marettimo, in the Egadi Islands off the coast of Italy, near the Province of Trapani.
In November 2010, a Mediterranean monk seal, supposedly aged between 10 and 20, has been spotted in Bodrum, Turkey.
On December 31, 2010, the BBC Earth news reported that the MOm Hellenic Society had located a new colony of seals on a remote beach in the Aegean Sea. The exact location was not communicated so as to keep the site protected. The society was appealing to the Greek government to integrate the part of the island on which the seals live into a marine protected area.
On March 8, 2011, the BBC Earth news  reported that a pup seal had been spotted on 7 February while monitoring a seal colony on an island in the southwestern Aegean Sea. Soon after, it showed signs of weakness and it was taken to a rehabilitation centre to try to save it. The aim is to release it back into the wild as soon as it is strong enough.
On June 24, 2011, the Blue World Institute of Croatia  filmed an adult female underwater in the northern Adriatic, off the island of Cres and a specimen of unverified sex on June 29, 2012. 

Saturday 28 July 2012

Kakapo

The Kakapo (Māori: kākāpō, meaning night parrot), Strigops habroptila (Gray, 1845), also called owl parrot, is a species of large, flightless nocturnal parrot endemic to New Zealand. It has finely blotched yellow-green plumage, a distinct facial disc of sensory, vibrissa-like feathers, a large grey beak, short legs, large feet, and wings and a tail of relatively short length. A certain combination of traits makes it unique among its kind—it is the world's only flightless parrot, the heaviest parrot, nocturnal, herbivorous, visibly sexually dimorphic in body size, has a low basal metabolic rate, no male parental care, and is the only parrot to have a polygynous lek breeding system. It is also possibly one of the world's longest-living birds. Its anatomy typifies the tendency of bird evolution on oceanic islands, with few predators and abundant food: a generally robust physique, with accretion of thermodynamic efficiency at the expense of flight abilities, reduced wing muscles, and a diminished keel on the sternum.
The Kakapo is critically endangered; as of February 2012, only 126 living individuals are known, most of which have been given names. The common ancestor of the Kakapo and the genus Nestor became isolated from the remaining parrot species when New Zealand broke off from Gondwana, around 82 million years ago. Around 70 million years ago, the kakapo diverged from the genus Nestor. In the absence of mammalian predators, it lost the ability to fly. Because of Polynesian and European colonisation and the introduction of predators such as cats, rats, ferrets, and stoats, the Kakapo was almost wiped out. Conservation efforts began in the 1890s, but they were not very successful until the implementation of the Kakapo Recovery Plan in the 1980s. As of April 2012, surviving Kakapo are kept on three predator-free islands, Codfish (Whenua Hou), Anchor and Little Barrier islands, where they are closely monitored. Two large Fiordland islands, Resolution and Secretary, have been the subject of large-scale ecological restoration activities to prepare self-sustaining ecosystems with suitable habitat for the Kakapo.
The conservation of the Kakapo has made the species well known. Many books and documentaries detailing the plight of the Kakapo have been produced in recent years, one of the earliest being Two in the Bush, made by Gerald Durrell for the BBC in 1962. A feature length documentary, The Unnatural History of the Kakapo won two major awards at the Reel Earth Environmental Film Festival. Two of the most significant documentaries, both made by NHNZ, are Kakapo - Night Parrot (1982) and To Save the Kakapo (1997). The BBC's Natural History Unit also featured the Kakapo, including a sequence with Sir David Attenborough in The Life of Birds. It was also one of the endangered animals that Douglas Adams and Mark Carwardine set out to find for the radio series and book Last Chance to See. An updated version of the series has been produced for BBC TV, in which Stephen Fry and Carwardine revisit the animals to see how they are getting on almost 20 years later, and in January 2009, they spent time filming the Kakapo on Codfish Island. Footage of a kakapo named Sirocco attempting to mate with Cawardine's head was viewed by millions worldwide, leading to Sirocco becoming "spokesbird" for New Zealand wildlife conservation in 2010, as part of the International Year of Biodiversity. The kakapo was featured in the documentary series South Pacific (known as Wild Pacific in US) episode Strange Islands, originally aired on June 13, 2009.
The Kakapo, like many other New Zealand bird species, was historically important to the Māori, the indigenous people of New Zealand, appearing in many of their traditional legends and folklore. It was hunted and used as a resource by Māori, both for its meat as a food source and for its feathers, which were used to make highly valued pieces of clothing. It was also sometimes kept as a pet.


Taxonomy, systematics and naming

 

The Kakapo was originally described by English ornithologist George Robert Gray in 1845. Its generic name is derived from the Ancient Greek strix, genitive strigos "owl", and ops "face", while its specific epithet comes from habros "soft", and ptilon "feather". It has so many unusual features that it was initially placed in its own tribe, Strigopini. Recent phylogenetic studies have confirmed the unique position of this genus as well as the closeness to the Kākā and the Kea, both belonging to the New Zealand parrot genus Nestor. Together, they are now considered a separate family within the parrots, Strigopidae. Within the Strigopidae, the Kakapo is placed in its own tribe, Strigopini. Earlier ornithologists felt that the Kakapo may be related to the ground parrots and Night Parrot of Australia due to their similar coloration, but this is contradicted by recent studies; rather, the cryptic color seems to be adaptation to terrestrial habits that evolved twice convergently.
The name "Kakapo" is the English transliteration of "kākāpō" which is derived from the Māori terms kākā ("parrot") + ("night"). The Polynesian term kākā and its variant ʻāʻā were the generic South Pacific terms for Psittacidae. For example, the native names of the Kākā, the extinct Black-fronted Parakeet (Cyanoramphus zealandicus) of Tahiti, and the New Zealand members of the genus Cyanoramphus are also derived from them.

Description

 

A year-old Kakapo on Codfish Island.


The Kakapo is a large, rotund parrot; the male measures up to 60 cm (24 in) and weighs from 2 to 4 kg (4 to 9 lb) at maturity. The Kakapo cannot fly, having short wings for its size and lacking the pronounced keel bone (sternum) that anchors the flight muscles of other birds. It uses its wings for balance, support, and to break its fall when leaping from trees. Unlike other land birds, the Kakapo can accumulate large amounts of body fat to store energy, making it the heaviest parrot.
The upper parts of the Kakapo have yellowish moss-green feathers barred or mottled with black or dark brownish grey, blending well with native vegetation. Individuals may have strongly varying degrees of mottling and colour tone and intensity — museum specimens show that some birds had completely yellow colouring. The breast and flank are yellowish-green streaked with yellow. The belly, undertail, neck and face are predominantly yellowish, streaked with pale green and weakly mottled with brownish-grey. Because the feathers do not need the strength and stiffness required for flight, they are exceptionally soft, giving rise to the specific epithet habroptilus. The Kakapo has a conspicuous facial disc of fine feathers, resembling the face of an owl; thus, early European settlers called it the "owl parrot". The beak is surrounded by delicate vibrissae or "whiskers", which the bird uses to sense the ground for navigation as it walks with its head lowered. The mandible is mostly ivory-coloured, with part of the upper mandible being bluish-grey. The eyes are dark brown. Kakapo feet are large, scaly, and, as in all parrots, zygodactyl (two toes face forward and two backward). The pronounced claws are particularly useful for climbing. The ends of the tail feathers often become worn from being continually dragged on the ground.
The "whiskers" around the beak.

The female is easily distinguished from the male: she has a more narrow and less domed head, her beak is narrower and proportionally longer, her cere and nostrils smaller, her legs and feet more slender and pinkish grey, and her tail proportionally longer. While her plumage colour is not very different to that of male, the toning is more subtle, with less yellow and mottling. She tends to resist more and be more aggressive than the male when handled. A nesting female also has a brood patch on the bare skin of the belly.
Like many parrots, the Kakapo has a variety of calls. As well as the booms  and chings of their mating calls, it will often skraark to announce its location to other birds.
The Kakapo has a well-developed sense of smell, which complements its nocturnal lifestyle. It can discriminate among odours while foraging; a behaviour reported for only one other parrot species. One of the most striking characteristics of the Kakapo is its pleasant and powerful odour, which has been described as musty. Given the Kakapo's well-developed sense of smell, this scent may be a social chemosignal. The smell often alerts predators to the largely defenseless Kakapo.

Anatomy

 

The skeleton of the Kakapo differs from other parrots in several features associated with flightlessness. Firstly, it has the smallest relative wing size of any parrot. Its wing feathers are shorter, more rounded, less asymmetrical, and have fewer distal barbules to lock the feathers together. The sternum is small, and has a low, vestigial, keel, and a shortened spina externa. As in other flightless birds and some other flighted parrots, the furcula is not fused, but consists of a pair of clavicles lying in contact with each coracoid. As in other flightless birds, the angle between the coracoid and sternum is enlarged. The Kakapo has a larger pelvis than other parrots. The proximal bones of the leg and arm are disproportionately long and the distal elements are disproportionately short.
The pectoral musculature of the Kakapo is also modified by flightlessness. The pectoralis and supracoracoideus muscles are greatly reduced. The propatagialis tendo longus has no distinct muscle belly. The sternocoracoideus is tendinous. There is an extensive cucularis capitis clavicularis muscle that is associated with the large crop.

Ecology and behaviour

 

Historic distribution of the Kakapo.
  Maximum distribution since 1840
  Fossil evidence

It seems that the Kakapo — like many of New Zealand's bird species — has evolved to occupy an ecological niche normally filled by various species of mammal (the only non-marine mammals native to New Zealand are three species of small bats). Before the arrival of humans, the Kakapo was distributed throughout the three main islands of New Zealand. It lived in a variety of habitats, including tussocklands, scrublands and coastal areas. It also inhabited forests, including those dominated by podocarps (rimu, matai, kahikatea, totara), beeches, tawa, and rata. In Fiordland, areas of avalanche and slip debris with regenerating and heavily fruiting vegetation — such as five finger, wineberry, bush lawyer, tutu, hebes, and coprosmas — became known as "Kakapo gardens".
The Kakapo is primarily nocturnal; it roosts under cover in trees or on the ground during the day and moves around its territories at night.
Though the Kakapo cannot fly, it is an excellent climber, ascending to the crowns of the tallest trees. It can also "parachute" - descending by leaping and spreading its wings. In this way it may travel a few metres (yards) at an angle of less than 45 degrees.
Having lost the ability to fly, it has developed strong legs. Movement is often by way of a rapid "jog-like" gait by which it can move many kilometres (miles). A female has been observed making two return trips each night during nesting from her nest to a food source up to 1 km (0.6 mi) away and the male may walk from its home range to a mating arena up to 5 km (3 mi) away during the mating season (October–January).
Young birds indulge in play fighting and one bird will often lock the neck of another under its chin. The Kakapo is curious by nature and has been known to interact with humans. Conservation staff and volunteers have engaged extensively with some Kakapo, which have distinct personalities.
The Kakapo was a very successful species in pre-human New Zealand and one of the reasons for this was their set of adaptations to effectively avoid predation from native birds of prey, which were their only predators in the past. However, these same behaviours have been of no use to them when faced with the mammalian predators which were introduced to New Zealand after human settlement, because these hunt in different ways. As hunters, birds behave very differently to mammals, relying on their powerful vision to find prey and thus, they usually, (with the exception of owls) hunt by day. Apart from the two surviving New Zealand raptors, the New Zealand Falcon and Swamp Harrier, there were two other birds of prey in pre-human New Zealand: Haast's Eagle and Eyles' Harrier. All four species soared overhead searching for prey in daylight and to avoid these avian predators, the Kakapo's ancestors adopted camouflaged plumage and became nocturnal. In addition, when the Kakapo feels threatened, it freezes, so that it is more effectively camouflaged in the forest vegetation which their plumage resembles. It was not entirely safe at night when the Laughing Owl was active and it is apparent from their nest deposits on Canterbury limestone cliffs that the Kakapo was among their prey.
Mammalian predators, in contrast to birds, rely on their sense of smell and hearing to find prey and often hunt by night. The Kakapo's adaptations to avoid avian predation have thus been useless against its new enemies - this is one of the reasons for its massive decline since the introduction of dogs, cats and mustelids - see Conservation: Human impact. A typical way for humans to hunt down the Kakapo is by releasing trained dogs.

Diet

 

The beak of the Kakapo is adapted for grinding food finely. For this reason, the Kakapo has a very small gizzard compared to other birds of their size. It is generally herbivorous, eating native plants, seeds, fruits, pollens and even the sapwood of trees. A study in 1984 identified 25 plant species as Kakapo food. It is particularly fond of the fruit of the rimu tree, and will feed on it exclusively during seasons when it is abundant. The Kakapo has a distinctive habit of grabbing a leaf or frond with a foot and stripping the nutritious parts of the plant out with its beak, leaving a ball of indigestible fiber. These little clumps of plant fibres are a distinctive sign of the presence of the bird. The Kakapo is believed to employ bacteria in the foregut to ferment and help digest plant matter.
Kakapo diet changes according to the season. The plants eaten most frequently during the year include some species of Lycopodium ramulosum, Lycopodium fastigium, Schizaea fistulosa, Blechnum minus, Blechnum procerum, Cyathodes juniperina, Dracophyllum longifolium, Olearia colensoi and Thelymitra venosa. Individual plants of the same species are often treated differently. The Kakapo leaves conspicuous evidence of their feeding activities, from 10×10 m (30×30 ft) to 50×100 m (160×300 ft) feeding ground areas. Manuka and yellow silver pine scrubs are obvious signs of its centre of feeding activities.

Reproduction

 

A Kakapo camouflaged by its feathers.
 
The Kakapo is the only species of flightless parrot in the world, and the only flightless bird that has a lek breeding system. Males loosely gather in an arena and compete with each other to attract females. Females listen to the males as they display, or "lek". They choose a mate based on the quality of his display; they are not pursued by the males in any overt way. No pair bond is formed; males and females meet only to mate.
During the courting season, males leave their home ranges for hilltops and ridges where they establish their own mating courts. These leks can be up to 7 kilometres (4 mi) from a Kakapo's usual territory and are an average of 50 metres (160 ft) apart within the lek arena. Males remain in the region of their court throughout the courting season. At the start of the breeding season, males will fight to try to secure the best courts. They confront each other with raised feathers, spread wings, open beaks, raised claws and loud screeching and growling. Fighting may leave birds with injuries or even kill them.
Each court consists of one or more saucer-shaped depressions or "bowls" dug in the ground by the male, up to 10 centimetres (4 in) deep and long enough to fit the half-metre length of the bird. The Kakapo is one of only a handful of birds in the world which actually constructs its leks. Bowls are often created next to rock faces, banks, or tree trunks to help reflect sound - the bowls themselves function as amplifiers to enhance the projection of the males booming mating calls. Each male’s bowls are connected by a network of trails or tracks which may extend 50 metres (160 ft) along a ridge or 20 metres (60 ft) in diameter around a hilltop. Males meticulously clear their bowls and tracks of debris. One way researchers check whether bowls are visited at night is to place a few twigs in the bowl; if the male visits overnight, he will pick them up in his beak and toss them away.
To attract females, males make loud, low-frequency (below 100 Hz) booming calls from their bowls by inflating a thoracic sac. They start with low grunts, which increase in volume as the sac inflates. After a sequence of about 20 loud booms, the male Kakapo emits a high frequency, metallic "ching" sound. He stands for a short while before again lowering his head, inflating his chest and starting another sequence of booms. The booms can be heard at least one kilometre (0.6 mi) away on a still night; wind can carry the sound at least five kilometres (3 mi). Males boom for an average of eight hours a night; each male may produce thousands of booms in this time. This may continue every night for three or four months during which time the male may lose half his body weight. Each male moves around the bowls in his court so that the booms are sent out in different directions. These booms are also notorious for attracting predators, because of the long range at which they can be heard.
Females are attracted by the booms of the competing males; they too may need to walk several kilometres from their territories to the arena. Once a female enters the court of one of the males, the male performs a display in which he rocks from side to side and makes clicking noises with his beak. He turns his back to the female, spreads his wings in display and walks backwards towards her. The duration of attempted copulation is between 2 to 14 minutes. Once the birds have mated, the female returns to her home territory to lay eggs and raise the chicks. The male continues booming in the hope of attracting another female.
The female Kakapo lays up to three eggs per breeding cycle. She nests on the ground under the cover of plants or in cavities such as hollow tree trunks. The female incubates the eggs faithfully, but is forced to leave them every night in search of food. Predators are known to eat the eggs and the embryos inside can also die of cold in the mother's absence. Kakapo eggs usually hatch within 30 days, bearing fluffy gray chicks that are quite helpless. After the eggs hatch, the female feeds the chicks for three months, and the chicks continue to remain with the female for some months after fledging. The young chicks are just as vulnerable to predators as the eggs, and young have been killed by many of the same predators that attack adults. Chicks leave the nest at approximately 10 to 12 weeks of age. As they gain greater independence, their mothers may feed the chicks sporadically for up to 6 months.
Because the Kakapo is long-lived, with an average life expectancy of 95 years and the maximum at about 120 years, it tends to have an adolescence before it starts breeding. Males do not start to boom until about 5 years of age. It was thought that females reach sexual maturity at 9 years of age; but this idea was debunked in the 2008 breeding season when two 6-year-old females named Apirama and Rakiura laid eggs. Generally females do not seek out males until they are between 9 and 11-years-old. The Kakapo does not breed every year and has one of the lowest rates of reproduction among birds. Breeding occurs only in years when trees mast (fruit heavily), providing a plentiful food supply. Rimu mast occurs only every three to five years, so in rimu-dominant forests such as those on Codfish Island, Kakapo breeding occurs as infrequently.
Another interesting aspect of the Kakapo's breeding system is that a female can alter the sex ratio of her offspring depending on her condition. A female that eats protein-rich foods produces more male offspring (males have 3%–40% more body weight than females). Females produce offspring biased toward the dispersive sex when competition for resources (such as food) is high and toward the non-dispersive sex when food is plentiful. A female Kakapo will likely be able to produce eggs even when there are few resources, while a male Kakapo will be more capable of perpetuating the species when there are plenty, by mating with several females. This supports the Trivers–Willard hypothesis. The relationship between clutch sex ratio and maternal diet has conservation implications, because a captive population maintained on a high quality diet will produce fewer females and therefore fewer individuals valuable to the recovery of the species.

Conservation

 

Fossil records indicate that in pre-Polynesian times, the Kakapo was New Zealand's third most common bird and it was widespread on all three main islands. However, the population of Kakapo in New Zealand has declined massively since human settlement of the country. Since 1891, conservation efforts have been made to prevent extinction. The most successful scheme has been the Kakapo Recovery Plan; this was implemented in 1989 and is still ongoing.

Human impact

 

The first factor in the decline of the Kakapo was the arrival of humans. Māori folklore suggests that the Kakapo was found throughout the country when the Polynesians first arrived in Aotearoa 700 years ago  subfossil and midden deposits show that the bird was present throughout the North Island, South Island and Stewart Island before and during early Māori times. Māori settlers from Polynesia hunted the Kakapo for food and for their skins and feathers, which were made into luxurious capes. They used the dried heads as ear ornaments. Due to its flightlessness, strong scent and habit of freezing when threatened, the Kakapo was easy prey for the Māori and their dogs. Its eggs and chicks were also predated by the Polynesian Rat or kiore, which the Māori brought to New Zealand. Furthermore, the deliberate clearing of vegetation by Māori reduced the habitable range for Kakapo. Although the Kakapo was extinct in many parts of the islands by the time Europeans arrived, including the Tararua and Aorangi Ranges, it was still present in the central part of the North Island and forested parts of the South Island.Beginning in the 1840s, European settlers cleared vast tracts of land for farming and grazing, further reducing Kakapo habitat. They brought more dogs and other mammalian predators, including domestic cats, black rats and stoats. Europeans knew little of the Kakapo until George Gray of the British Museum described it from a skin in 1845. As the Māori had done, early European explorers and their dogs ate Kakapo. In the late 19th century, the Kakapo became well known as a scientific curiosity, and thousands were captured or killed for zoos, museums and collectors. Most captured specimens died within months. From at least the 1870s, collectors knew the Kakapo population was declining; their prime concern was to collect as many as possible before the bird became extinct.
In the 1880s, large numbers of mustelids (stoats, ferrets and weasels) were released in New Zealand to reduce rabbit numbers, but they also preyed heavily on many native species including the Kakapo. Other browsing animals, such as introduced deer, competed with the Kakapo for food, and caused the extinction of some of its preferred plant species. The Kakapo was reportedly still present near the head of the Whanganui River as late as 1894, with one of the last records of a Kakapo in the North Island being a single bird caught in the Kaimanawa Ranges by Te Kepa Puawheawhe in 1895.

Early protection efforts

 

In 1891, the New Zealand government set aside Resolution Island in Fiordland as a nature reserve. In 1894, the government appointed Richard Henry as caretaker. A keen naturalist, Henry was aware that native birds were declining, and began catching and moving Kakapo and kiwi from the mainland to the predator-free Resolution Island. In six years, he moved more than 200 Kakapo to Resolution Island. By 1900, however, stoats had swum to Resolution Island and colonised it; they wiped out the nascent Kakapo population within 6 years.

Thousands of Kakapo were collected for museums across the world
 
In 1903, three Kakapo were moved from Resolution Island to the nature reserve of Little Barrier Island north-east of Auckland, but feral cats were present and the Kakapo were never seen again. In 1912, three Kakapo were moved to another reserve, Kapiti Island, north-west of Wellington. One of them survived until at least 1936, despite the presence of feral cats for part of the intervening period.
By the 1920s, the Kakapo was extinct in the North Island and its range and numbers in the South Island were declining. One of its last refuges was rugged Fiordland. There, during the 1930s, it was often seen or heard, and occasionally eaten, by hunters or roadworkers. By the 1940s, reports of Kakapo were becoming scarce.


1950–1989 conservation efforts

 

Sinbad Gully in Fiordland, seen between the mountains on the far side of a fjord, was one of the last strongholds of the Kakapo on mainland New Zealand
 
In the 1950s, the New Zealand Wildlife Service was established and began making regular expeditions to search for the Kakapo, mostly in Fiordland and what is now the Kahurangi National Park in the northwest of the South Island. Seven Fiordland expeditions between 1951 and 1956 found only a few recent signs. Finally, in 1958 a Kakapo was caught and released in the Milford Sound catchment area in Fiordland. Six more Kakapo were captured in 1961; one was released and the other five were transferred to the aviaries of the Mount Bruce Bird Reserve near Masterton in the North Island. Within months, four of the birds had died and the fifth died after about four years. In the next 12 years, regular expeditions found few signs of the Kakapo, indicating that numbers were continuing to decline. Only one bird was captured in 1967; it died the following year.
By the early 1970s, it was uncertain whether the Kakapo was still an extant species. At the end of 1974, scientists located several more male Kakapo and made the first scientific observations of Kakapo booming. These observations led Don Merton to speculate for the first time that the Kakapo had a lek breeding system. From 1974 to 1976, 14 Kakapo were discovered but all appeared to be males. One male bird was captured in the Milford area in 1975, christened "Richard Henry", and transferred to Maud Island. This raised the possibility that the species would become extinct, because there might be no surviving females. All the birds the Wildlife Service discovered from 1951 to 1976 were in U-shaped glaciated valleys flanked by almost-vertical cliffs and surrounded by high mountains. Such extreme terrain had slowed colonisation by browsing mammals, leaving islands of virtually unmodified native vegetation. However, even here, stoats were present and by 1976 the Kakapo was gone from the valley floors and only a few males survived high on the most inaccessible parts of the cliffs.
Before 1977, no expedition had been to Stewart Island/Rakiura to search for the bird. In 1977, sightings of Kakapo were reported on Stewart Island. An expedition to the island found a track and bowl system on its first day; soon after, it located several dozen Kakapo. The finding in an 8,000 ha area of fire-modified scrubland and forest raised hope that the population would include females. The total population was estimated at 100 to 200 birds.
Mustelids have never colonised Steward Island/Rakiura, but feral cats were present. During a survey, it was apparent that cats killed Kakapo with a predation rate of 56% per annum. At this rate, the birds could not survive on the island and therefore an intensive cat control was introduced in 1982, after which no cat-killed Kakapo were found. However, to ensure the survival of the remaining birds, scientists decided later that this population should be transferred to predator-free islands; this operation was carried out between 1982 and 1997.

Kakapo recovery plan

 

Kakapo Translocations 1974–1992
Translocated to Number of Kakapo Deaths < 6 months Survived as of November 1992
Maud Island (1974–81) 9 (6♂, 3♀) 3 (2♂, 1♀) 4 (2♂, 2♀)
Little Barrier Island (1982) 22 (13♂, 9♀) 2 (1♂, 1♀) 15–19 (10–12♂, 5–7♀)
Codfish Island (1987–92) 30 (20♂, 10♀) 0 20–30 (13–20♂, 7–10♀)
Maud Island (1989–91) 6 (4♂, 2♀) 0 5 (3♂, 2♀)
Mana Island (1992) 2 (2♀) 1 (1♀) 1 (1♀)
Total 65 (43♂, 22♀) 6 (3♂, 3♀) 41–55 (27–36♂, 14–19♀)
Note: ♂ = males, ♀ = females.

In 1989, a Kakapo Recovery Plan was developed and a Kakapo Recovery Group established to implement it. The New Zealand Department of Conservation replaced the Wildlife Service for this task. The first action of the plan was to relocate all the remaining Kakapo to suitable islands for them to breed. None of the New Zealand islands were ideal to establish Kakapo without rehabilitation by extensive revegetation and the eradication of introduced mammalian predators and competitors. Four islands were finally chosen: Maud, Hauturu/Little Barrier, Codfish and Mana. Sixty-five Kakapo (43 males, 22 females) were successfully transferred onto the four islands in five translocations. Some islands had to be rehabilitated several times when feral cats, stoats and weka kept appearing. Little Barrier Island was eventually viewed as unsuitable due to the rugged landscape, the thick forest and the continued presence of rats, and its birds were evacuated in 1998. Along with Mana Island, it was replaced with two new Kakapo sanctuaries, Chalky Island (Te Kakahu) and Anchor Island. The entire Kakapo population of Codfish Island was temporarily relocated in 1999 to Pearl Island in Port Pegasus while rats were being eliminated from Codfish. All Kakapo on Pearl and Chalky Islands were moved to Anchor Island in 2005.

Cat control in 1982 arrested a sharp decline in Kakapo numbers, and they have recently increased under the Kakapo Recovery Plan. Red arrows indicate breeding years. Numbers become less precise before 1995, with the 1977 figure perhaps out by 50 birds.
 
A key part of the Recovery Plan is the supplementary feeding of females. The Kakapo breeds only once every two to five years, when a certain type of plant species, primarily Dacrydium cupressinum (rimu), produces protein-rich fruit and seeds. Observations of the relationship between intermittent breeding and the plant's mast year help biologists choose which suitable supplementary foods to increase Kakapo breeding frequency. In 1989, six preferred foods (apples, sweet potatoes, almonds, brazil nuts, sunflower seeds and walnuts) were supplied ad libitum each night to 12 feeding stations. Males and females ate the supplied foods, and females nested on Little Barrier Island in the summers of 1989–91 for the first time since 1982, although nesting success was low.
Supplementary feeding not only increases Kakapo breeding frequency, but also affects the sex ratio of Kakapo offspring, as maternal conditions influence this ratio. This finding was subsequently used to increase the number of female chicks by deliberately manipulating maternal condition. During the winter of 1981, only females below 1.5 kg weight were given supplementary feeding to avoid raising their body condition, and the sex ratio results in 1982 were close to parity, eliminating the male-biased sex ratios in the unrestricted feeding.
Though breeding can be improved by supplementary feeding, the survival of young Kakapo is hampered by the presence of Polynesian rats. Of 21 chicks that hatched between 1981 and 1994, nine were either killed by rats or died and were subsequently eaten by rats. Nest protection has been intensified since 1995 by using traps and poison stations as soon as a nest had been detected. A small video camera and infra-red light source watch the nest continuously, which will remotely scare approaching rats by small bang and flash lights. To increase the success rate of nesting, a nest watcher places a small thermostatically controlled electric blanket over the eggs or chicks, whenever the female leaves the nest for food. The survival rate of chicks has increased from 29% in unprotected nests to 75% in protected ones.
To monitor the Kakapo population continuously, each bird is equipped with a radio transmitter. Every known Kakapo, barring some young chicks, has been given a name by Kakapo Recovery Programme officials. It is an affectionate way for conservation staff to refer to individual birds, and a stark reminder of how few remain. Artificial incubation of eggs and hand-raising of chicks have often been used to improve the condition of the eggs and chicks. In November 2005, the population comprised 41 females and 45 males, including four fledgings (3 females and 1 male) bred in 2005. The oldest known Kakapo, "Richard Henry", was thought to be 80 years old at the time of his death in December 2010.
In 2006, the Kakapo Recovery Programme presented a new management plan that would run from 2006 to 2016. The key goals of this plan are to increase the female population to at least 60 by 2016, increase genetic diversity, maintain or restore a sufficiently large habitat to accommodate the expected increase in the Kakapo population, and maintain public awareness and support.
The Kakapo Recovery Plan has been a successful programme, with the numbers of Kakapo increasing steadily. Adult survival rate and productivity have both improved significantly since the programme's inception. However, the main goal is to establish at least one viable, self-sustaining, unmanaged population of Kakapo as a functional component of the ecosystem in a protected habitat. To help meet this conservation challenge, two large Fiordland islands, Resolution (20,860 ha) and Secretary (8,140 ha), have been prepared for re-introduction of the Kakapo with large-scale ecological restoration activities.
During the 2008-2009 summer breeding season, the total population of Kakapo rose to over 100 for the first time since monitoring began, reaching 126 by February 2012. More than twenty of the 34 chicks had to be hand-reared because of a shortage of food on Codfish Island.
In 2012, seven Kakapo were transferred to Little Barrier Island, in an attempt to establish a successful breeding program. Kakapo were last on the island in 1998.

In Māori culture

 

The Kakapo is associated with a rich tradition of Māori folklore and beliefs. The bird's irregular breeding cycle was understood to be associated with heavy fruiting or "masting" events of particular plant species such as the Rimu which led Māori to credit the bird with the ability to foretell the future. Used to substantiate this claim were reported observations of these birds dropping the berries of the Hinau and Tawa trees (when they were in season) into secluded pools of water to preserve them as a food supply for the summer ahead; in legend this became the origin of the Māori practice of immersing food in water for the same purpose.

Use for food and clothing

 

The meat of Kakapo made good eating and was considered by Māori to be a delicacy and it was hunted for food when it was still widespread. One source states that its flesh "resembles lamb in taste and texture", although European settlers have described the bird as having a "strong and slightly stringent flavour".
In breeding years, the loud booming calls of the males at their mating arenas made it easy for Māori hunting parties to track the Kakapo down, and it was also hunted while feeding or when dustbathing in dry weather. The bird was caught, generally at night, using snares, pitfall traps, or by groups of domesticated Polynesian dogs which accompanied hunting parties — sometimes they would use fire sticks of various sorts to dazzle a bird in the darkness, stopping it in their tracks and making the capture easier. Cooking was done in a hāngi or in gourds of boiling oil. The flesh of the bird could be preserved in its own fat and stored in containers for later consumption — hunters of the Ngāi Tahu tribe would pack the flesh in baskets made from the inner bark of Totara tree or in containers constructed from kelp. Bundles of Kakapo tail feathers were attached to the sides of these containers to provide decoration and a way to identify their contents. Also taken by the Māori were the bird's eggs, which are described as whitish "but not pure white", and about the same size as a kererū egg.
As well as eating the meat of the Kakapo, Māori would use Kakapo skins with the feathers still attached or individually weave in Kakapo feathers with flax fibre to create cloaks and capes. Each one required up to 11,000 feathers to make. Not only were these garments very beautiful, they also kept the wearer very warm. They were highly valued, and the few still in existence today are considered taonga (treasures) — indeed, the old Māori adage "You have a Kākāpō cape and you still complain of the cold" was used to describe someone who is never satisfied. Kakapo feathers were also used to decorate the heads of taiaha, but were removed before use in combat.
Despite this, the Kakapo was also regarded as an affectionate pet by the Māori. This was corroborated by European settlers in New Zealand in the 19th century, among them George Edward Grey, who once wrote in a letter to an associate that his pet Kakapo's behavior towards him and his friends was "more like that of a dog than a bird".