To bleed or not to bleed, that is the question.

nature reserve in the Saudi Arabian desert. It has been a dry winter, with virtually no rain since the previous spring.The hoopoe larks are quiet this year. Occasionally a male whistles his song and dances vertically up and down in the air – about 5 metres up, then, after a somersault , back to the ground or the bush that he started from. In some years, every territory contains a dancing male. In the flat desert landscape you can see them from afar and hear them everywhere. Early April 2000.After two days of sandstorms that built up our expectations, the rains are a disappointment. The rain gauges that are spread throughout the reserve and the puddles in the tyre tracks tell us that some hoopoe lark territories have received up to 10 millimetres, others next to nothing.We imagine a pair of hoopoe larks in a dry territory watching the rain come down a few kilometres away; should they move over there and try to supplant the territory owners? Whether they should or not, they don't. We have never observed hoopoe larks moving to areas where the grass is greener; instead they wait till next year. For hoopoe larks in the Arabian Desert rain is an important cue that appears to have both short-and long-term consequences, depending on its timing. The patchy and limited rainfall of April 2000 triggered a short-term response in lark pairs living in the territories that actually did receive rain: males started displaying enthusiastically, while females dug nest cups and began gathering sticks. But after a few days, before nest construction was completed, the urge had passed. Apparently rain acted as a cue to start breeding behaviour but whatever the next 154 19 C h a p t e r To breed or not to breed: that is the question IRENE TIELEMAN AND JOE WILLIAMS Decisions facing hoopoe larks in the Arabian desert In temperate areas, we tend to take it for granted that birds have an annual cycle that includes a breeding season each spring. Temperate zone passerines predictably produce one or more clutches of eggs every year. But hoopoe larks and other small desert birds will sometimes skip a breeding season. This seems a major decision in the life of a small bird, especially considering the short life span of small animals. How can we get insights into the decision-making processes of desert breeding birds? …