I haven't updated this blog in a long while, so this is just a quick update.
I completed the vegetation surveys around the nests and also for the random plots. Nest #10 survived for at least two days, at which time I was able to obtain measurements to show the growth of the young. Unfortunately it was empty after three more days, a likely victim of predation. Nest success is indeed quite low for lark sparrows at Sand Prairie.
Starting tomorrow I will be visiting Sand Prairie for four straight days, hoping to record the vocalizations of singing birds. I already have some songs of post-breeding males but not nearly as many as I would like.
Monday, July 16, 2012
Tuesday, July 3, 2012
More Nests
I haven't updated this blog in a while. I have still been kept busy, however, conducting vegetation surveys and searching for nests. I completed three more random plot surveys last week, but thanks to today's discoveries, it looks like I will be conducting a few more.
My main focus today was to record the songs of post-breeding males, a rather difficult task considering the inconsistency with which birds sing in the middle to late summer months. Before hiking to check on nest #5, I decided to explore the dunes near the parking lot, where my friend Whitney and I had seen a lone sparrow egg sitting in the sand the week before. The egg was still there, the shell intact but the contents within no longer present. A clump of panic grass was nearby and I lifted it to reveal an abandon lark sparrow nest, nest #9. I will be conducting a survey of the surrounding vegetation this Thursday.
Nest #5 still held two eggs. Nevertheless I still fear that the nest has been abandoned, simply because of the amount of time they've been there. Upon my return to the sand washes I observed a pair of birds copulating and decided to follow them to see if they were nesting. Assuming the birds to be territorial (which all available evidence leads to), I had been seeing this pair for the past month and their last nesting attempt had failed. One of the birds led me to its new nest, a soft green caterpillar in its beak ready to feed the newborn chicks. They weighed less than 3 grams and were likely only 1-2 days old. An egg also remained unhatched. I am holding out hope that these birds survive and fledge.
My main focus today was to record the songs of post-breeding males, a rather difficult task considering the inconsistency with which birds sing in the middle to late summer months. Before hiking to check on nest #5, I decided to explore the dunes near the parking lot, where my friend Whitney and I had seen a lone sparrow egg sitting in the sand the week before. The egg was still there, the shell intact but the contents within no longer present. A clump of panic grass was nearby and I lifted it to reveal an abandon lark sparrow nest, nest #9. I will be conducting a survey of the surrounding vegetation this Thursday.
Nest #5 still held two eggs. Nevertheless I still fear that the nest has been abandoned, simply because of the amount of time they've been there. Upon my return to the sand washes I observed a pair of birds copulating and decided to follow them to see if they were nesting. Assuming the birds to be territorial (which all available evidence leads to), I had been seeing this pair for the past month and their last nesting attempt had failed. One of the birds led me to its new nest, a soft green caterpillar in its beak ready to feed the newborn chicks. They weighed less than 3 grams and were likely only 1-2 days old. An egg also remained unhatched. I am holding out hope that these birds survive and fledge.
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