Known as a bird with a light iris, the Rusty Blackbird is uncommon and can be found in Oklahoma in winter, if you are lucky. Though drab and a loner, they once darkened the skies, much like the now extinct Passenger Pigeon.
A breeding bird of the boreal forest, this blackbird has been declining in population since the middle of last century for unestablished reasons. One possibility is the loss of habitat in wintering regions in the southeast, where most of the species is located during that time.
Birds of the northeast have been showing high concentrations of mercury, not unusual where coal happens to be a source of heat and powering electrical plants. If that fossil fuel becomes reestablished, chances are good that it will destroy the remaining populations, unless it relocates itself elsewhere.
Rusty Blackbirds forage on the ground and will wade in water in order to turn over leaves and twigs while seeking insects, which could also have high mercury concentrations. Some of Oklahoma's lakes and other larger bodies of water can be suspect, especially around the Sooner Lake power plant, which is still partially coal fired.
Rusty Blackbird
Boomer Lake Park, 2016
Logging in the winter ranges around bogs, fens and other wet methane reaches of spaghnum moss, the mechanical sound of a rusty hinge can be heard. This is the sound of the Rusty Blackbird, which was once ubiquitous at the turn of the 1900s.
Climate change is no doubt playing a part in the loss of this population. The rain comes and goes, their favorite invertebrates choked out by their loss of habitat, excess heat and cold, or any other negative effects. Either their food departs for cooler or warmer climates as the seasons change, or they migrate to possibly even less favorable conditions.
Acid rain is likely another suspect in some of this mystery, because it was caused by the combustion of fossil fuels. It is due to the emission of sulfur dioxide and nitrogen oxides. Also, we must look at the effects of toxic algal blooms, which destroys ecosystems that these birds favor, and that's where pesticide runoff will accumulate, which can also kill the inhabitants of these systems. A stronger case is the Dead Zone in the Gulf of Mexico, which is spreading to their wintering areas.
What is most necessary is the preservation of crucial wetlands, less disturbance, and more birders to seek out their habitats and report their findings to the International Rusty Blackbird Working Group during select spring migrations and on eBird.
In the winter, the rusty seeks pine seeds, acorns, and whatever available fruit it can locate.
They can be found on edges of lakes or ponds, in pecan orchards, agricultural areas, flooded forests, swamps, flooded roadside ditches, and the like.
Rusty Blackbird(s) have been seen during most winters at Sanborn or Boomer Lakes from 2013-2018.
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