Andaman Spiny Shrew

The Andaman Spiny Shrew is a small insectivorous mammal endemic to South Andaman Island in the Bay of Bengal, India. It is one of the least-known shrew species in the world, known from only a handful of specimens. Its restricted range and rarity make it a species of significant conservation concern. It is notable for its coarse, spiny-textured fur, a distinguishing feature among Crocidura species.

South Andaman Island, India

Endemic to South Andaman Island in the Andaman Archipelago, Bay of Bengal, India. Known only from a very limited number of localities, making it one of the most geographically restricted shrew species. No records exist outside this single island.

Altitude and depth

Likely found at low to moderate elevations typical of South Andaman Island, roughly 0-460m, though precise altitudinal data is lacking due to scarcity of records.

This species inhabits tropical moist evergreen forest on South Andaman Island, likely favoring dense leaf litter and undergrowth typical of insular tropical forest ecosystems. Little direct habitat data exists, but closely related shrews in the region are associated with humid forest floor environments.

Adaptations to its environment

Like other Crocidura shrews, it likely possesses a high metabolic rate and continuous feeding behavior to sustain its small body size. Its coarse or 'spiny' fur may provide some protection in dense forest litter environments where it forages.

Classified as Vulnerable (VU) by the IUCN due to its extremely restricted range, being known only from South Andaman Island, combined with ongoing habitat degradation. The species' rarity and lack of recent confirmed records raise concerns about its population status.

Estimated population

No reliable population estimate exists; the species is known from very few museum specimens and sightings, suggesting a small and possibly declining population, though trend data is largely unknown.

Main threats include deforestation and habitat conversion for agriculture and settlement on Andaman Island, as well as potential impacts from introduced species and infrastructure development. Its narrow endemic range makes it highly vulnerable to any localized habitat loss.

Some protection may be afforded indirectly through forest reserves and protected areas on South Andaman Island, though no species-specific conservation program is known to exist for this shrew. It falls under general biodiversity protection laws of the Andaman and Nicobar Islands.

Recommended actions

Priority actions include dedicated field surveys to assess current population status and distribution, habitat protection for remaining forest patches on South Andaman Island, and further taxonomic and ecological research to inform conservation planning.

The species has a coarse, somewhat spiny or bristly fur texture, giving rise to its common name, with a typical shrew-like elongated snout, small eyes, and short limbs. Fur coloration is likely brownish-grey, consistent with related Crocidura species in the region.

Size

Body length (head-body) is estimated at approximately 60-80mm, consistent with other small Crocidura shrews, though precise measurements from limited specimens are not well documented.

Weight

Weight is estimated to be in the range of 4-10 grams, typical for small Crocidura species, though exact data specific to this species is scarce.

Distinctive features

It is distinguished from other Andaman shrews primarily by its distinctively coarse or spiny fur texture, along with subtle cranial and dental characteristics used in taxonomic identification. These features separate it from the more common Crocidura andamanensis found on the same islands.

Presumed to be solitary, as is typical for most Crocidura shrew species, with minimal social interaction outside of breeding encounters.

When it is active

Likely nocturnal or crepuscular, consistent with the general activity pattern of shrews, though specific behavioral data for this species is lacking.

Diet

Presumed insectivorous diet consisting of small invertebrates such as insects, larvae, and other arthropods found in leaf litter, similar to other Crocidura species.

How it feeds and hunts

Likely forages by actively probing leaf litter and soil with its sensitive snout to locate small invertebrate prey, using a high-metabolism foraging strategy typical of shrews.

Communication

Likely communicates through ultrasonic vocalizations and scent marking typical of shrews, used for territory delineation and possibly mate attraction, though specific studies are lacking.

Interactions with other species

Potential predators may include forest birds, snakes, and small carnivorous mammals present on South Andaman Island. It may compete with other small insectivores, including the sympatric Crocidura andamanensis, for similar food resources.

Role in its ecosystem

As an insectivore, it likely plays a role in controlling invertebrate populations within its forest habitat, contributing to the balance of the forest floor ecosystem on South Andaman Island.

Reproductive biology is essentially undocumented, but based on related Crocidura species, breeding likely involves short gestation periods of around 3-4 weeks and litters of 2-4 young.

Raising the young

Parental care is presumed to be provided solely by the female, as in most shrew species, involving nursing and protection of young in a nest until weaning.

Maturity and lifespan

Specific data is unavailable, but based on related Crocidura species, sexual maturity is likely reached within a few months, with a wild lifespan probably not exceeding 1-2 years.

Classification

Class Mammalia > Order Eulipotyphla > Family Soricidae > Genus Crocidura > Species Crocidura hispida

Recent studies

Very few recent studies have focused specifically on this species due to its rarity; most information derives from historical taxonomic descriptions and museum specimens, highlighting a need for updated field research.

Compared with similar species

Compared to the more widespread Crocidura andamanensis, C. hispida is distinguished by its coarser fur texture and more restricted distribution, being known from far fewer localities and specimens.

This shrew is so rarely recorded that it is sometimes considered one of the most poorly known mammals in India. Its 'spiny' common name refers to its unusually coarse fur, a rare trait among shrews.

Where and how to see it

Due to its extreme rarity and elusive nocturnal habits, observing this species in the wild is exceptionally difficult; any potential sighting would require dedicated small-mammal trapping surveys in remaining forest habitat on South Andaman Island.

Risks to humans

No notable risk to humans.