He never did have Martins in the homemade house, but it was the beginning of learning more about them. He didn’t know much about them, really didn’t even know what they looked like! Occasionally a squawking bird would show up and look over the house Dave was pretty sure it was a Martin, but the bird never stayed. Dave built it, put it in his back yard and waited for the birds to show up. The MDC produced a booklet that had different types of housing for different types of birds… including a plan for a Purple Martin house. One of the most enjoyable things for him was to see wild birds using his homemade boxes! Dave found a lot of plans from the Missouri Department of Conservation. He made a lot of extra Bluebird and Wren houses, and gave them out as Christmas presents. The adults wait patiently on adjacent nest trees with mouths full of dragonflies and cicadas, chirping away.Dave Hartwig always enjoyed doing wood working projects, especially making bird boxes. In fact, we often have quite the audience watching while we quickly and carefully lower and check the nests. Fortunately, martins are incredibly comfortable around people. The Purple Martin Conservation Association found that less than 45% of nestlings in parasite-infested nests survived to fledgling age. Without this kind of help, purple martin colonies can begin to decline. We discard the wet, dirty nest full of mites and carefully transfer the chicks to the new clean, dry nest. If we find a nest with mites, we quickly prepare a clean plastic gourd with soft pine bedding and pine straw. They can also cause adults to stop bringing food to the nest, leading birds to leave the nest too early. While not interested in humans, mites will feed on nestlings. Parasites, such as mites, are also a common issue. The chicks hatch after about 15 days, and both parents feed them for four to five weeks until they fledge (leave the nest). Martins can have up to seven eggs in a clutch, laying one egg every 24 hours. We check all 132 nest cavities once a week to record signs of nests, the number of eggs laid and how many chicks hatched. We monitor our purple martins from their arrival in March through the end of August. We hope these 12 birds will return next year - and bring some friends along with them! On April 21, we finally had our first arrival. Purple martins prefer to nest together, so the dummy bird and songs entice young martins flying by to stop in and investigate the housing. Hoping to attract them this year, we added a “dummy” bird (a plastic bird that looks like a purple martin) and played recordings of purple martin calls. It can take anywhere from a few days to a couple of years to attract martins to new housing, and no birds moved in for the first few years. This smaller colony is about 2 miles east of the first, in an area of SCBI that houses rare and endangered ungulates (hoofed animals), like Persian onagers and Eld’s deer. In 2018, we set up a second purple martin tower with 24 more nest cavities. The colony has 108 nest cavities and was first erected in the 1980s by Smithsonian biologist Gene Morton, who led many research projects on martins over the years. Over the next few weeks, 180-200 more birds moved into the colony at the center of our campus. This year, our first scout (a lone adult male) arrived March 25. Scouts are simply older birds returning to the places where they successfully nested before. The first birds to arrive are often called “scouts.” Contrary to popular belief, they are not sent ahead to scout nesting sites on behalf of their group. We also set up predator safeguards to deter raptors and snakes. In preparation for their arrival, we clean plastic nest gourds and hang them on metal nesting tree racks. Martins make their way to Virginia in mid-March and start nesting in May. But dedicated purple martin landlords have likely slowed the rate of this decline by helping the birds thrive during the breeding season. They have experienced a steady decline over the last several decades due to the widespread use of pesticides and competition from invasive species. Purple martins are important native birds that help control insect populations by eating bugs. It means the birds have returned from their South American wintering grounds! That includes our bird team here at the Smithsonian Conservation Biology Institute in Front Royal, Virginia. Each year, purple martin “landlords” anxiously await the loud, throaty chirps and rattle songs of purple martins (Progne subis).
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