Procyon Pygmaeus

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in biology, Procyon Pygmaeus (Alias:Cozumel Raccoon or Pygmy Raccoon or Dwarf Raccoon or Cozumel Island Raccoon and Cozumel Raccoon Bear) It is an animal of the family Procyonidae and the genus Procyon. The fur is mainly tan with scattered dark hairs. There is a thick mask of dark fur around the eyes, with distinct white fur on each side. Their tails are golden-toned and divided by 6 to 7 rings of dark fur. The Cozumel raccoon is the smallest member of the genus Procyon. The average weight of adult males is 3.58±0.52 kg, and the average weight of females is 3.28±0.18 kg. Males are about 11% heavier than females. The average total head and body length of an adult Cozumel raccoon is 75.5 centimeters, accounting for approximately 90% of the total length of species on the mainland. Likewise, the average tail length of males is 24.4 cm and that of females is 24.2 cm. The size of their canine teeth varies greatly between the sexes, with the average male canine length being 10.8 millimeters and the average female canine length being just 9.9 millimeters.

Found only on the Mexican island of Cozumel, it usually inhabits mangrove swamps and other coastal areas. It is omnivorous and feeds mainly on crabs, but also fruits, insects, frogs and lizards.

Clinton Hart Merriam first described the Cozumel raccoon as morphologically distinctive from its mainland relative, the common raccoon subspecies Procyon lotor hernandezii, in 1901. Since then, other scientists have generally agreed with Merriam's assessment, especially Kristofer Helgen and Don E. Wilson, who have dismissed this classification for the other four island raccoons in their studies in 2003 and 2005. Therefore, the Cozumel raccoon was listed as the only distinct species of the genus Procyon besides the common raccoon and the crab-eating raccoon in the third edition of Mammal Species of the World. An archeological study showed that Maya from Cozumel used raccoons of reduced stature, which suggests that the size reduction of this raccoon is not a recent phenomenon.

No true fossils of the species are known, although skeletons have been found at some archeological sites on the island. Cozumel island itself separated from the mainland during the late Pleistocene, so that the species is unlikely to be older than 122,000 years. Data from molecular clock studies implies a divergence date from the common raccoon of anywhere between 26,000 and 69,000 years ago.

The Cozumel raccoon is similar in appearance to the North American raccoon (Procyon lotor). The fur is mainly tan with scattered dark hairs. There is a thick mask of dark fur around the eyes, with distinct white fur on each side. Their tails are golden-toned and divided by 6 to 7 rings of dark fur. The Cozumel raccoon is the smallest member of the genus Procyon. The average weight of adult males is 3.58±0.52 kg, and the average weight of females is 3.28±0.18 kg. Males are about 11% heavier than females. The average total head and body length of an adult Cozumel raccoon is 75.5 centimeters, accounting for approximately 90% of the total length of species on the mainland. Likewise, the average tail length of males is 24.4 cm and that of females is 24.2 cm. The size of their canine teeth varies greatly between the sexes, with the average male canine length being 10.8 millimeters and the average female canine length being just 9.9 millimeters.

The Cozumel raccoon is found on Cozumel Island, located on the coast of the Yucatan Peninsula in Mexico. The island is located at the junction of the Gulf of Mexico and the Caribbean Sea, 16 kilometers away from the Yucatan Peninsula in Mexico.

Cozumel raccoons prefer mangrove forests and sandy areas, but are also found in semi-evergreen and semi-deciduous tropical forests and agricultural areas. The abundance of different vegetation types varies greatly. Most of the population lives in the coastal areas of the island, and most of the central part of the island is free of Cozumel raccoons or has low densities. Cozumel raccoons may live near human settlements or on paved and unpaved roads.

social behavior

Cozumel raccoons are mostly nocturnal, although they can sometimes be seen during the day. They build nests as shelter, but unlike most other raccoon species, they do not hibernate due to their subtropical habitat. Cozumel raccoons have the ability to climb trees. The back feet can rotate 180 degrees, which allows them to descend first from the top of a tree. Cozumel raccoons are usually solitary, but sometimes individuals form groups or temporary gatherings during the mating season or to exploit food sources associated with humans.

The Cozumel raccoon's territory is estimated to be approximately 67 hectares. The size of their territory is usually based on the availability of food. Where there is more food, the territory is smaller; where there is no food, the territory is larger.

Cozumel raccoons, like all other members of the genus Procyon, use their senses to communicate. Cozumel raccoons generally use their sense of touch more than other animals. Cozumel raccoons lack opposable thumbs and their claws cannot retract. Their sensitive front paws are used for handling and cleaning food or other objects. Cozumel raccoons have corrected vision, with poor distance vision but good night vision. Their vision is not as important as their sense of smell. Cozumel raccoons use their keen sense of smell to detect the presence of predators or prey as well as food. Odoriferous glands (usually anal glands) as well as urine and feces are used as chemical markers to distinguish individuals from conspecifics. Cozumel raccoons also have an enhanced sense of hearing, which allows them to communicate well with each other. Cozumel raccoons produce vocalizations that include hisses, howls, growls, hisses, screams, and whimpers. These vocalizations are used for intraspecific and interspecific communication.

feeding behavior

Cozumel raccoons are omnivorous and feed on a variety of plants and animals. More than 50% of their diet consists of crab. Other food sources include fruits, insects, crayfish, frogs, and other vertebrates and invertebrates, as appropriate. Seeds from the fruit of Sapodilla (Manilkara achras) and flowering plants of the pea family, as well as leaves from panicles of the genus Grass, were found in the feces. There are few differences in feeding behavior across seasons, locations, genders and age groups. However, their diet can also change after significant changes in habitat quality due to natural or man-made destruction of the habitat. Hurricanes can reduce the proportion of crabs in the diet and increase the proportion of invertebrates and other food sources.

Like other raccoons, Cozumel raccoons are polygamous. During the mating season, males and females usually congregate in certain areas during a 3-4 day receptive period. During this time, the male mates with as many females as possible, and the female will mate with multiple males. Females breed once a year during one of two breeding seasons. Most are born between November and January. Therefore, the breeding interval is September and November. However, some pups are born in late summer in July-August, with a breeding interval of May-June. After a gestation period of 63-65 days, each litter gives birth to 2-5 offspring, each weighing approximately 60-75 grams. Females usually reach sexual maturity in about 1 year, and males in about 2 years.

Males do not participate in raising the young. The male and female take care of the young alone until weaning and teach the young how to survive on their own. Pups are usually weaned at about 16 weeks of age. Pups become independent at about 10 months of age, however, in some cases, the offspring stay with their mother for a short period immediately after sexual maturity but eventually disperse to find a mate.

protection level

Listed in the "World Conservation Union Red List of Threatened Species" (IUCN 2016 ver 3.1) - Critically Endangered (CR).

Listed on the Mexican National Endangered Species List (SEMARNAT 2010) - Endangered (En Peligro de Extinción).

Population status

The species is considered critically endangered due to its small numbers (limited to one island) and concentrated populations, with all individuals comprising only one subpopulation. Although multiple population estimates exist, the typical total population estimated for Cozumel raccoons in the wild is less than 250 mature individuals, and all studies indicate that the population is declining. While the actual numbers are likely to be very resilient over time (given population fluctuations around tropical hurricanes), the general trend is that they are limited to very small numbers due to continued human encroachment (tourism, urban growth, development) Habitat fragmentation is characterized by rapid declines in mature individuals, invasive species (predators and pathogens), expansion of roads, and increasing intensity and severity of hurricanes.

Estimates of the total subpopulation of Cozumel raccoons, including juveniles, range from 323 (McFadden 2004) to 955 (Copa-Alvaro 2007) individuals. Considering that 59.4% of captured individuals were adult raccoons (McFadden & Mairi, 2013), the estimated number of mature individuals was 192–567. Density estimates vary by location and year, ranging from 12.4-112 individuals/km2 (McFadden 2004, Copa-Alvaro 2007). The ratio of males to females is quite balanced. McFadden et al. conducted a subsample survey at two locations in 2010. Among the 96 captured Cozumel raccoons, 47 were males and 49 were females. However, García-Vasco (2005) found that the ratio was slightly skewed towards women, but not significantly different from 1:1.

The species is severely affected by hurricanes, and population numbers fluctuate with these events. It is increasingly difficult for the species to recover after these natural disasters, as human activities have severely squeezed the population. After a major hurricane, Cozumel raccoon densities in specific locations can drop by as much as 60%, and young raccoons can significantly reduce their proportion in the population (Copa-Alvaro 2007). The effects of hurricanes may vary between different areas of the island or between vegetation types (Copa-Alvaro 2007).

Cause of Endangerment

The island of Cozumel has been extensively developed for tourism. Until around 2005, Cozumel was relatively well protected, with nearly 90% of the island covered by natural vegetation (Romero-Nájera 2004, Romero-Nájera et al. 2007), but the situation deteriorated rapidly. The interior of the island is less developed, but Cozumel raccoons are rare or absent (Cuarón et al., 2004; García-Vasco, 2005; Copa-Alvaro, 2007). Cozumel only has a small patch of raccoon habitat, and it's on the coast where most tourism is developing.

The expansion and widening of the road system fragmented the island's vegetation in at least three areas (Cuarón et al., 2004; de Villa-Meza et al., 2004, 2011). Widening the road may increase its barrier effect and exacerbate its impacts on Cozumel raccoons and other native species (de Villa-Meza et al., 2011). Most documented Cozumel raccoon deaths since 2001 have been caused by being run over by cars on the island's highways (García-Vasco 2005).

Invasive exotic predators, such as snakes and pythons, as well as domestic and wild dogs, may all have important impacts on Cozumel's raccoon populations, and wild dogs have been shown to predate them (Martínez-Morales & Cuarón 1999, García-Vasco 2005, Bautista 2006). Additionally, introduced predators may easily serve as a source of parasites and pathogens that may negatively impact Cozumel raccoon bear populations (Cuarón et al. 2004; McFadden et al. 2005; Mena 2007). Introduced North American raccoons, frequently carried on ferries between the island and the mainland, present a risk of genetic introgression and are a potential source of parasites and pathogens (Cuarón et al., 2004).

Hurricanes are the main natural threat to raccoons in Cozumel (Cuarón et al., 2004; Perdomo, 2006; Barillas, 2007; Copa-Alvaro, 2007). For the Cozumel raccoon bear, hurricanes can cause drastic reductions in their numbers, reduce the proportion of juveniles, directly harm and promote pathological changes (Copa-Alvaro 2007, Mena 2007). The frequency, intensity and duration of hurricanes in the Caribbean basin are increasing (Goldenberg et al., 2001), so this is a major concern because of possible synergistic effects with anthropogenic disturbances.

Safeguard

Cozumel raccoons are legally protected in Mexico under an island-wide Programa de Ordenamiento Ecologico Local, which aims to identify patterns of land occupation and minimize conflicts among stakeholders. Conflict and maximize consensus. The plan is in the process of being formally promulgated. Steps are being taken to create two new protected areas on the island of Cozumel. An invasive exotic animal control program is underway on the island. The program mainly targets urban stray cats and dogs. Also establish a captive breeding program. An environmental education program promotes the conservation of Cozumel's endemic biota. An interdisciplinary, multi-institutional team in Mexico has developed, promoted and sustained a long-term program to study and conserve native organisms in Cozumel. These measures help improve Cozumel raccoon habitat and population (Cuaron et al. 2009)

Cozumel raccoons are infected with several diseases and parasites that can be transmitted to humans. Most of these diseases originate from domestic animals. Toxoplasma gondii, a parasitic protozoan that causes toxoplasmosis, has been found in some people. Cozumel raccoons are particularly susceptible to pathogens and diseases, such as manger, rabies, and distemper. Some people have developed antibodies against some of these diseases. All of these diseases can pose a threat to humans, but because Cozumel's raccoon population is so small, the chance of disease spreading from Cozumel's raccoons to humans is slim. In the past, when Cozumel's raccoon population levels were much higher, occasional crop damage occurred.