Topic : Land Birds
Article 39 26 October 2007
Pratincoles – unusual breeding behaviour
One normally associates Collared Pratincole Glareola pratincola nesting sites with low lying ground close to water and little or no surrounding vegetation. In KwaZulu-Natal, South Africa, there are at least two to three known sites where this species breeds in ploughed, newly planted or cut sugar cane fields. These regularly used sites may not necessarily be adjacent dams or pans and are often a couple of kilometers from the nearest source of water.
One such site where these birds nest annually is between the towns of Mtunzini and Gingindlovu where the birds return annually in August to breed on fallow fields little more than 40 – 50 m.a.s.l. Egg laying then takes place at the end of August or during September/October. The eggs are placed on flat ground (no hollow scrape) and the chicks fledge before the sugar cane crop reaches one foot high.
Red-winged Pratincoles are listed as ‘Rare’ and ‘Near-threatened’ birds whose range has contracted in southern Africa in the past century. The most southern breeding birds on the continent is at the Umvoti River mouth, approximately 54 kilometers further south. During the spring of 2007, seven pairs of these birds bred at the abovementioned site, though in 2002, an estimated 15 – 20 pairs bred in an adjacent field.
Pratincoles are aerial feeders, and at these small unusual breeding colonies they are known to forage at dusk above the cultivated sugar cane fields. It could be possible that they benefit from the presence of flying Eldana moths Eldana saccharina that are nocturnal. The eldana borer is the larval stage of a small brown moth that is indigenous to Africa and is normally hosted by a number of indigenous grasses and sedges such as Cyperus papyrus and Cyperus dives. However, this insect has become the most serious pest in the South African sugar industry and is responsible for enormous damage to mature sugar cane stands, particularly when the cane is subjected to drought stress.
Acknowledgments. Mr Gaby Maitre is thanked for allowing us to monitor these birds on his sugar cane farm. Mr Gary Lagerwall is acknowledged for the supply of information on the Eldana moth.