Status and distribution of the angonoka tortoise (Geochelone yniphora) of western Madagascar

From 1993 to 1995, field surveys were conducted in western Madagascar to as sess the current status of the angonoka tortoise (Geochelone yniphora) in t he wild. Tortoise presence was documented at 10 of 11 localities surveyed. These localities represent at least five populations, all within a 30-km ra dius of Baly Bay, near the town of Soalala. The populations occur on fragme nts of habitat ranging from < 50 to 4-6000 ha in size. One hundred and fort y-five tortoises were marked in the five populations. Hatchling or juvenile tortoises were observed in all populations, indicating that reproduction w as occurring. Most of the 145 tortoises (68%) were marked on Cape Sada, whe re monthly surveys were conducted. The tortoise density on the c. 150 ha pe ninsula was 0.66 tortoises/ha. The remains of 22 dead juveniles were found on Cape Sada over the 2-year period. This evidence, combined with the low n umber of juveniles in intermediate size classes in the Cape Sada population suggests that juvenile mortality may be high. (C) 1999 Elsevier Science Lt d. All rights reserved.