Birds of southeast Texas in photos

1. Plan to count birds for at least 15 minutes on one or more days of the count. You can count for longer than that if you wish! Count birds in as many places and on as many days as you like—one day, two days, or all four days. Submit a separate checklist for each new day. You can also submit more than one checklist per day if you count in other locations on that day.

2. Count the greatest number of individuals of each species that you see together at any one time. You may find it helpful to print out your regional bird checklist to get an idea of the kinds of birds you’re likely to see in your area in February. You could take note of the highest number of each species you see on this checklist.

3. When you’re finished, enter your results through our web page. You’ll see a button marked “Enter Your Checklists!” on the website home page beginning on the first day of the count. It will remain active until the deadline for data submission. (We’ll let you know when that is for 2012.)

The Great Backyard Bird Count

As summer heats up, the sight of blooming thistles may give male goldfinches a testosterone kick.

Thistle flowers could signal to American goldfinches that the seeds the songbirds prize for baby food and parent food will soon be abundant, proposes Thomas Luloff of the University of Western Ontario in London, Canada. And in lab setups, male goldfinches housed among blooming Canadian thistles underwent physiological changes that indicate the birds got the “breed now” message from the combination of summery heat and thrilling thistles, Luloff reported January 6 at the annual meeting of the Society for Integrative and Comparative Biology. read more

Like gangsters running a protection racket, drongos in the Kalahari Desert act as lookouts for other birds in order to steal a cut of their food catch. The behaviour, revealed in research funded by BBSRC published in Evolution and reported in Nature’s Research Highlights today (18 November), may represent a rare example of two species evolving from a parasitic to a mutualistic relationship.

The team from the Universities of Bristol, Cambridge and Cape Town showed that victimised pied babblers gained a mitigating benefit from the presence of thieving drongos because, by keeping watch for predators, the drongos allowed the babblers to focus on foraging and so catch more insects.

Dr Andrew Radford, who led the research funded through a BBSRC David Phillips Fellowship, said: “Because drongos are parasitic birds who swoop in to steal food from other species, you’d expect them to keep a low profile while waiting. Rather surprisingly, however, drongos perched above foraging babblers advertise their presence by issuing a call called a ‘twank’ every 4 or 5 seconds.

“When we played back these ‘twank’ calls to a babbler group, we found that they spread out over a larger area and lifted their heads less often, indicating that they were less fearful of predators when they thought a drongo was keeping watch. We think that drongos have evolved to alert babblers to their presence because helping the group forage more effectively leads to more frequent opportunities for theft.”

Drongos have an ingenious way of catching food: by crying wolf about the presence of predators, they scare other animals into dropping their catch, which the birds then pounce on. This research indicates that pied babblers have evolved to tolerate the drongos giving false warnings and stealing some of their hard-earned gains in exchange for the chance to forage in relative safety when a drongo is keeping watch.

Dr Radford continued: “Like any good gangster, as well as lying and stealing, the drongos also provide protection by mobbing aerial predators and giving true alarm calls on some occasions. But, despite all of the useful services drongos provide, the foraging birds are still more responsive to calls from other babblers. It seems likely that the babblers simply don’t trust the drongo mafia as much as their own flesh and blood.”

Professor Douglas Kell, BBSRC Chief Executive said: “Evolutionary arms-races, including those between parasites and their hosts, and plants and animals and the diseases that they suffer, underlie a whole range of socially and economically important areas of biology. From drug and pesticide resistance to the biodiversity of ecosystems, deepening our understanding how a range of organisms have evolved into complex relationships will help us address important social issues in a smarter, more holistic way.”
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(source) Gangster birds running protection racket give insight into coevolution

Singing for your supper