Rusty Blackbirds are the Poster Birds for North America’s declining bird populations. In the last 40 years their populations have declined 75% across their range & plummeted 85-99% in some localities. This is even more rapid than their cousins in the Grasslands category of species that is leading the decline in North American bird populations. 53%, 700M, of the 3B birds lost between 1970 and 2019 were Grassland birds.
The exact reasons that Rusties are declining at a faster rate than their taxonomic cousins is not fully understood. On the surface, they do appear to be more vulnerable to the threats to the wooded wetlands they prefer and not capable of competing with the other blackbirds, such as Red-winged Blackbirds & Common Grackles, for the shrinking and lower water quality wetlands. But why is that? Scientists don’t know. There is a scarcity of data to inform an understanding of the root-cause problems.
If scientists don’t know then it follows that conservation policy makers do not either. This is obviously an issue for planning and building sustainable conservation management programs. This raises yet another why-question. Why the data scarcity? As with many problems, there are multiple reasons, but I think there is an issue common to scarcity of data problems – a scarcity of research funding. Given the order of magnitude of the decline and the obvious signaling that something is desperately wrong across large swaths of North American habitat – habitat we cohabitate with the declining bird populations – yet another why-question arises. Why is funding not following the problem?
One reason is perhaps the simple lack of celebrity status in a celebrity obsessed world. Rusty Blackbirds are not majestic. They are not wetland icons. And perhaps worse they are not cute. If they were a ‘birb’ things might be different.
The fact is they, and many of their Grassland cousins, are perceived on the opposite end of the ‘birb’ spectrum. Though declining rapidly, they are still among our most numerous birds. They are considered ‘common’, with all the connotations that entails. Their large flocks are often considered pests, prone to decimating crops and pooping on public spaces, across their range. In many states, policy and programs are not about conservation, but controlling these pests. Harassment, even killing, can be permitted if the landowner deems there is or will be substantial damage to crops or ornamental plantings. As more evidence of their stature, when Canada and the U.S. signed a treaty to protect migratory birds more than a century ago, blackbirds were left out of the agreement.
Without question, large blackbird flocks can be a pain in the arse. However, there doesn’t seem to be a matching of severity of the ‘bad bird problem’ with the severity of the consequences of well-intentioned pest control programs, especially if these consequences are not understood in the context of: loss of wetlands, insect apocalypse, the evaporation of breeding ground ponds due to climate change, lead poisoning, mercury poisoning …. All happening in parallel over the last fifty years.
With the total impact not recorded. Totally unnoticed. That is until 1999 when Russell Greenberg and his coauthor Sam Droege published On the Decline of the Rusty Blackbird in Conservation Biology. They had noticed in their field work that they were seeing fewer and fewer Rusties. They searched literature to see why this might be. Only to, guess what?, discover there was no field data specific to Rusty Blackbird surveys from breeding or non-breeding grounds. Turning to Christmas Bird Counts, Breeding Bird Surveys, references to the species in the literature, regional checklists, and historical survey and with some modeling they estimated that Rusty Blackbird populations had precipitously declined 90% since the mid-20th century. It is a number that doesn’t have to be dead-on accurate. It is a classic example of asking even asking “what if it’s 50% wrong?”, there is a problem. A big problem with lots of spillover potential.
Since the publication of this paper there has been more focused, Rusty specific research. As well as research on more of the Grassland ‘favorites’, such as Eastern Meadowlarks (which is not a lark, but a blackbird with color and a pleasant, moody whistle). More data is leading to more insights and input to policy. Including, the North American Grassland Conservation Act that is moving its way through Congress and significant program funding in the 2023 Farm Bill.
There is still a lot to be done and it all needs data to be grounded in reality. Scientists have formed a Rusty Blackbird Working Group to analyze the declines & formulate conservation programs’ input. Their efforts can be amplified by citizen scientists. Specifically, they can rely on citizen scientist data collected & reported on eBird to broaden the and deepen the range of understanding of what is going on across “large swaths of North American habitat – habitat we cohabitate with the declining bird populations”.
Help them out when you can & keep a look out for Rusties & your eBird checklists updated. Do it for the Rusties and do it for ourselves.