Geocapromys ingrahami (J. A. Allen, 1891)

Don E. Wilson, Thomas E. Lacher, Jr & Russell A. Mittermeier, 2016, Echimyidae, Handbook of the Mammals of the World – Volume 6 Lagomorphs and Rodents I, Barcelona: Lynx Edicions, pp. 552-604 : 555

3.

Ingraham’s Hutia

Geocapromys ingrahami

French: Hutia des Bahamas / German: Bahama-Ferkelratte / Spanish: Jutia de Bahamas

Other common names: Bahaman Hutia, Bahamian Hutia

Taxonomy. Capromys ingrahami J. A. Allen, 1891 ,

“Plana Keys, Bahamas.”

This species is monotypic.

Distribution. Bahamas, only known from the type locality in East Plana Cay. Introduced into Little Wax Cay in 1973 and on Warderick Wells Cay in 1981, also in Bahamas.

Descriptive notes. Head-body 280-320 mm, tail 55 mm. No specific data are available for body weight. Ingraham’s Hutia is small, with soft, pale grayish, brownish, or buff dorsal fur. Lateral lower parts of ears and cheeks are usually paler or brighter. Venter is brighter than dorsum. Unlike the Jamaican Hutia ( G. brownii ), cream spots are usually absent, or only rarely present, on venter and are rarely present, which is distinctive, between front limbs and hindlimbs. Tail length is equal to or longer than hindfeet and ¢.20% of head-body length. Ears are naked, with two long tufts on dorsal margins. Skull has no inflated frontal. Alveolar length of maxillary tooth is less than 165 mm. Basicranium is broad and dorso-ventrally curved compared with that of the Jamaican Hutia. Zygomatic arch is situated above cheekteeth laterally, with a jugal spine. Sagittal and temporal crests are weakly developed. Long jugular process is curved anteriorly and reaches mid-level of bulla tympanica. Tympanic bullae are inflated, and palatal spine is absent. Teeth similar in shape to those of the Jamaican Hutia.

Habitat. Semiarid habitats of woody shrubs and thickets on East Plana Cay coral atoll. Ingraham’s Hutia lives in underground crevices or caves and under leaf piles ofsilver palm trees ( Coccothrinax argentata, Arecaceae ). It does not nest or burrow but has scansorial locomotion and is a good climber.

Food and Feeding. Ingraham’s Hutias forage in trees, primarily on leaves, but they eat large amounts of phloem by eating bark. In Little Wax Key, they have overexploited their habitat and caused local extirpation of four tracheophytic species. Diets includes more than 40 plant species, with main food items including leaves of Coccoloba diversifolia ( Polygonaceae ), Manilkara bahamensis ( Sapotaceae ), Sophora tomentosa (Fabaceae) , and Zanthoxylum coriaceum ( Rutaceae ). Diets in other studies have contained 44-4% of the subclass Asteridae, including Boraginaceae (Tournefortia gnaphalodes), Convolvulaceae ( Ipomoea batatas), Oleaceae ( Forestiera segregata), and Rubiaceae ( Strumpfia maritima); 33-3% of the subclass Rosidae such as Combretaceae ( Conocarpus erectus), Euphorbiaceae (Phyllanthus epiphyllanthus and Croton lucidus); 11-1% Papaya ( Carica papaya, Caricaceae ); and 11-1% cactus. Ingraham’s Hutias also occasionally forage on algae on the beach, sea shoal, and human leftovers. They apparently stand on hindlimbs to reach leaves on low-lying shrubs and use their hand pads to manipulate and grasp food. They seem to be adapted to arid habitats by being able to resist water stress and requiring less water than rainforest hutia species. Ingraham’s Hutias may also be able to tolerate drinking saltwater for more than a week.

Breeding. Ingraham’s Hutias breed throughout the year. Litter size is apparently only a single young that can weigh up to 80 g.

Activity patterns. Ingraham’s Hutia is strictly nocturnal and spends most ofits active period foraging.

Movements, Home range and Social organization. A previously captured female Ingraham’s Hutia was recaptured five years later only 20 m from its initial capture site on East Plana Cay Island. Both data points suggested relatively long life spans during which individuals move very little. On East Plana Cay Island over several years, density was high at up to 30 ind/ha. Despite high density, no conflicting or antagonistic behaviors were observed. Ingraham’s Hutia is primarily solitary and nocturnal, butit is non-territorial and has high intraspecific social tolerance; it may often occur in pairs (15 pairs were kept in captivity). Male Ingraham’s Hutias tend to be antagonistic toward other males, particularly when females are in estrus. Marking behavior was studied in laboratory. Ingraham’s Hutias use urine signaling and individuals seem to preferentially mark those previously marked rather than unmarked individuals. Both sexes mark wood sticks, and reproductive condition (estrus) was not a significant factor in marking behavior. Male Ingraham’s Hutias have more odorous urine than females. Overall, urine marking appears to be non-agonistic, which might be important for social organization.

Status and Conservation. Classified as Vulnerable on The IUCN Red List. Ingraham’s Hutia is poorly known and needs to be appropriately assessed. It has been extirpated from its native island and has been extirpated over most ofits distribution. Nevertheless, it may be locally abundant on the three small islands where it remains. Population sizes 25-30 years ago were estimated at 12,000 individuals on East Plana Key but only 1200 individuals on Little Wax Key. Updated ecological studies are required to confirm current conservation status of Ingraham’s Hutia.

Bibliography. Allen (1891), Borroto (2002), Borroto & Woods (2012a), Buden (1986), Chapman (1901), Clough (1972, 1974), Howe (1974), Jordan (1989), Woods (1982), Woods & Howland (1979), Woods etal. (2001).

Figures

1. Hispaniolan Hutia (Plagiodontia aedium), 2. Jamaican Hutia (Geocapromys brownu), 3. Ingraham’s Hutia (Geocapromys ingrahami), 4. Desmarest’s Hutia (Capromys pilorides), 5. Cabrera’s Hutia (Mesocapromys angelcabrerai), 6. Eared Hutia (Mesocapromys auritus), 7. Black-tailed Hutia (Mesocapromys melanurus), 8. Dwarf Hutia (Mesocapromys nanus), 9. Prehensile-tailed Hutia (Mysateles prehensilis), 10. Garrido Tree Hutia (Mysateles garridoi), 11. Groove-toothed Spiny-rat (Carterodon sulcidens)

Distribution. Bahamas, only known from the type locality in East Plana Cay. Introduced into Little Wax Cay in 1973 and on Warderick Wells Cay in 1981, also in Bahamas.