Nesting biology and food habits of the endangered Sakalava Rail Amaurornis olivieri in the Mandrozo Protected Area,western Madagascar§

We studied the nesting biology and food habits of the endangered and endemic Sakalava Rail Amaurornis olivieri from July to November 2015 in the Mandrozo Protected Area, western Madagascar. Three nesting pairs were observed and their nests were constructed in a dense mat of reeds Phragmites mauritianus and averaged 56.7 ± 15.3 cm above the water (n = 3 nests). Nests were built by both adults and it took 3 d on average to complete a nest (n = 2 nests). Thirteen matings were observed and lasted 4.1 s on average (n = 2 pairs). Average clutch size was three eggs (n = 2 nests). Both sexes incubated; the incubation period was 15–17 d (n = 2 nests). Both male and female participated in brooding and feeding the young, which remained for 3 d in the nest and became independent of their parents at 45 d of age. Based on 194 identified food items, the Sakalava Rail’s diet was composed of invertebrates: spiders (53.1%), insects (32%), crustaceans (10.8%) and molluscs (4.1%). The home ranges of two radio-tagged individuals were 0.95 and 1.98 ha.     

THE PROBLEM OF THE EVALUATION OF ROTENONE-CONTAINING PLANTS

A study has been made of the rotations of the resins from three types of derris root, and of a fraction rich in toxicarol separated from two of them. No strictly quantitative relationship between their rotations and their toxicities to Aphis rumicis has been found. The addition of caustic potash in methyl alcohol to the benzene solutions of the resins induces a characteristic change from laevo- to dextro-rotation in the samples rich in toxicarol. The induced dextro-rotation then declines in value with time. This effect is shown by the "toxicarol" resin. The rate of the decline is accelerated by increasing the amount of methyl alcohol.
We are greatly indebted to the Copper Technical Bureau for gifts of the "Sumatra-type" root and of resins derived from this strain.
We wish to express our thanks to Mr C. Read for help during the course of this work.