VOLUME 18 - N. 2

Abstract:

Very little published information exists concerning the reproductive biology of Dupont's Lark, Chersophilus duponti, and what is available largely refers to the North African population. Here we present data frorn 33 nests found in southeastern (n= 15) and centraI (n= 16) Spain between 1989 and 1993. The reproductive period extended frorn mid March lo early July, a month longer than the orth African populations. The laying peri od in SE Spain started more than a monrh earlier than in centraI Spain. Nests were placed on the ground, nearly always partially covered by shrubs (88 %), and oriented to the W, or E (84%) of the closest plant. In SE Spain, this species appears to select nest site positions covered by shrubs 7-12 cm in height. o selection was evident in centraI Spain, where shrub height rnay be closer IO the optirnurn required. Mean clutch size (3.6±0.6 sd) was larger than that reported for North Africa, but no differences were found between the two areas in Spain. lndications ofasynchronous hatching were found, and appear to depend on clutch size. Mean egg length and width were 0.5 mrn greater than those reported previously. The incubation peri od was 12-13 days. Nestling period was very short (8 days). est mortality was extremely high (84%), but egg hatchability was high (95.7%), and no nestlings starved (n=32). Coleopteran and lepidopteran larvae forrn 50%. of nestling diet, bui araneids (especially Lycosidae) are particularly important early in the nestling periodo