ALBINO COMMON FROG, RANA
IN I P S W I C H H . MENDEL
One of the more interesting natural history enquiries at Ipswich Museum in 1989 was a translucent yellow frog with dull, almost glowing pink eyes. It was found in a pit about 18 inches deep beneath a standpipe cover in the Wolsey Garden, Christchurch Mansion, Ipswich in October. Judging by its emaciated condition it had been there some time, probably surviving on the few insects which feil into the same trap. Adrian Mingay, the Christchurch Park gardener who found the frog, recognised it as something unusual and showed it to Park Ranger, Michael Stagg who brought it to the Museum. It was clearly an albinotic Common Frog rather than some unusual alien species, as first was suspected. The discovery of this frog caused considerable local interest and a colour photograph appeared in the Evening Star on Wednesday, October 25th, 1989. As a result, I was contacted by Mr. J. J. Thackeray who said he had bred from a pair of.similar frogs which were found in a drainage Channel on Suffolk Road, not far from Christchurch Park c. 1985. The eggs they produced had a white 'nucleus' and the tadpoles on hatching were white with pink eyes. These frogs were released in the Colchester Road area when Mr Thackeray moved house. The Common Frog is extremely variable in colour and no two individuals are exactly alike. The species is well known for its ability to change colour according to its surroundings and in response to temperature, humidity and light intensity. According to Smith (1973) there are three kinds of pigment cells which lie in the deeper layers of the skin: lipophores (containing yellowish pigments), guanophores (packed with whitish chrystals) and melanophores (containing melanin) responsible for the black or brown colouration. Albinism or partial albinism in the Common Frog is unusual and there are few published records. Knight (1980) described an adult male, found on 20th March 1979 in a garden in the Portsdown Hill area of Hampshire. It was very similar to the Ipswich specimen (a female without trace of black pigment) except that it had distinct, black nuptial pads which were shed on the 30th March the same year. Ely (1985) recorded a Leeds garden pond with albino frogs breeding in it and Ellis (1984) described albino frog tadpoles from a pond at Sprowston, Norfolk. The Sprowston tadpoles that survived produced 'orange-coloured frogs whose eyes lack dark pigment and have a strangely reflective glitter'. Partial ablinotic specimens with dark eyes also sometimes occur. Elkan (1972) reported a 'light orange' frog in which 'only the eyes are black'. Unfortunately the photograph published with his letter is black and white. The Ipswich frog fed greedily on crickets bought from a local pet shop and started to gain weight. However, it later lost condition, perhaps because of lack of variety in its diet, and died in January, 1990. It is preserved in Ipswich Museum.
Trans. Suffolk Nat. Soc. 26 (1990)
A L B I N O COMMON FROG, RANA
L. IN IPSWICH
Acknowledgements I thank John Buckley for pointing out references to other occurrences of albinism in frogs. References Elkan, E. (1972). Letter. British Journal of Herpetology, 4, 271. Ellis, E. A . (1984). Deathly pale. In the countryside. Eastern Daily Press, Ist August. Ely, W. A . (1985). Letter. British HerpetologicalSociety Bulletin, 12, 46. Knight, N. (1980). Albino male Rana temporaria with black nuptial pads. British Journal of Herpetology, 6, 67. Smith, M. (1973). The British amphibians and reptiles. Fifth edition. London: Collins. H . Mendel, The M u s e u m , High Street, Ipswich, IP1 3 Q H
Crayfish at West Stow I was pleased to learn from Richard D a r r a h , a ranger at West Stow Country Park, that a large crayfish (Astracus fluviatilis) had been seen in the River Lark there at the end of 1989. This lobster-like crustacean is the largest invertebrĂ¤te occurring in British fresh water, with a body up to 10cm or more. It only occurs in well oxygenated water and the river has clearly recovered f r o m the accidental contamination by an overflow from the Beet Sugar Factory at Bury St. E d m u n d s which occurred three years ago. Crayfish are brown (red only after cooking), with fused head and thorax and a b d o m e n ending in a tail fan. The front pair of Walking legs bear pincers. Crayfish generally live in holes in the bank and feed mainly on animal material, insects, worms and the like. T h e only ones I have seen in Suffolk came f r o m the river at Cavendish. Can readers teil me where they occur now? Geoff. Heathcote
Trans. Suffolk Nat. Soc. 26 (1990)
Plate 1: Common Frog, Rana lemporaria.
This albinotic specimen was found in Ipswich (p. 6). (Photo: East Anglian Daily Times)