The northern palm squirrel (Funambulus pennantii) is native to India, Iran, Nepal and Pakistan, but is now also found in Afghanistan. It was introduced into the grounds of the Perth Zoo in 1898 (Sedgewick 1968) and remained confined to the gardens for many years, but from about 1960 they had expanded into or been taken into a number of surrounding suburbs. A population also existed at Wesley College from about 1964, but did not increase much. Colonies also existed at Royal Perth Golf Club, South Perth Civic Centre, Comer Reserve, Como Primary School, Bentley Pine Plantation, McCallum Park and Raphael Park. In 1981 some were found a Midvale (Zekulich 1981) and at Kelmscott. At about the same time three were caught at Pingelly, having been transported in the roof of a transportable home. In 1984 single squirrel was trapped at Osborne Park (Long 1988).

The squirrel is the size of a very large rat (body mass about 135g, but up to 200g), it has light brown-to-grey fur on the head, ears and feet and deep red-brown or brown-grey fur on the back with five white longitudinal stripes on its back, three of which run for the head to the tail. It has a long fluffy tail, which it often holds erect. It eats seed, leaves and soft fruits, but unlike some other squirrels does not cache food. The northern palm squirrel can significantly damage fruit and vegetables, and would be a serious pest in orchards, nurseries and vineyards, if it were to become established in these areas in Western Australia.

It is gregarious and typically nests in trees, and was often seen running around the Perth Zoo and on the Royal Perth Golf Course. Its habitat preference is quite plastic and in its home land, is found in grasslands, scrublands, plantations and dry deciduous forests. It also inhabited the houses and parklands in the vicinity of the Perth Zoo, and because it was highly mobile and an excellent climber, backyard fences were never an obstacle as it moved from house-to-house.

Of interest, a Queensland Department of Employment, Economic Development and Innovation (2010) publication on the Indian Palm Squirrels indicated that they were being sold in NSW as pets. They were also established in an area within a 5km radius of Taronga Park Zoo (Watts and Aslin 1981), but died out some time later. The Department of Agriculture and Food (DAFWA) has the northern palm squirrel listed as number 4 on its Declared Animal Species priority list. Dr Peter Mawson (Director of Animal Health and Research) at the Perth Zoo indicated that the northern palm squirrel has almost been eradicated from the Perth Zoo by the zoo’s Black Rat control program. He indicated that none had been seen in the Zoo grounds for about 12 months, which suggests they are extinct at the Perth Zoo or the population is below a detectable level.

DAFWA also undertook a northern palm squirrel eradication program on the Royal Perth Golf Course in 2014, which also appears to have been successful. Darrel Stewart, DAFWA Biosecurity Officer, indicated that there may still be a few left on the golf course and possibly one down at the Old Mill. DAFWA plan another trapping program early next year to clean up the remaining individuals.

This is a great result for the hard work by Perth Zoo and DAFWA staff. It is not often we can come out in public and say we are close to the eradication of a vertebrate feral pest that has been established in Perth for over 100 years.

Information on the location of individuals provided for this post by Dr Peter Mawson at the Perth Zoo is appreciated.

References

Department of Employment, Economic Development and Innovation (2010) Indian Palm squirrels (Funambulus spp.). Unpublished report available online

Long, J.L. (1988). Introduced Birds and Mammals of Western Australia. Technical Series No. 1, second edition. Agriculture Protection Board of Western Australia.

Sedgwick, L.E. (1968). The Squirrels of South Perth. West. Aust. Nat. 11(1): 1-4.

Watts, C.H.S. and Aslin, H.J. (1981). Rodents of Australia. Angus and Robertson, Sydney and Melbourne.

Zekulich, M. (1981). Stray squirrels pose threat. West Australian, July 20, 1981.

Image credits – (top) – Department of Agriculture and Food website; (bottom) – Wikipedia.org