Image courtesy of Google Images.
When thinking a bit more about starlings and other “invasive” species (‘cause that is what I think about in my spare time apparently), a few more things about our current “issues” with invasive species came to mind I thought I would discuss.
One of the major problems (or advantages if you are the critter) with invasive species – in fact, part of what makes them invasive – is their lack of natural predators. Not that they won’t be predated – but the diseases and predators that have adapted to a diet of English Sparrows and European Starlings are in, well, Europe. This allows for their populations to explode if the food sources are plentiful, which here in the US of A, they are.
Another interesting issue that I think contributes to our invasive bird problems are our interesting ways of protecting birds. Not long ago, when we were bringing birds over from Europe, any song bird was a protected species – i.e. you couldn’t just kill it. The designation of song bird included pretty much any bird that wasn’t predatory – this included starlings, sparrows, red winged blackbirds, and other birds we now consider nuisances. Predatory birds on the other hand – hawks, eagles, owls, etc. – were fair game. These birds could be killed at will and with their tendency to predate on things we didn’t want them to predate, we looked to the skies through a gun barrel quite readily. As one can imagine, this led to a rapid decline in the populations of predatory birds – this along with our expanding cities and later “suburbia” really helped do them in.
Today, things have changed. Birds like starlings, sparrows, and pigeons are considered pests; they are no longer protected, and thus can be killed at will. Predatory birds, however, cannot. The tables have been flipped.
An interesting thing about these predatory birds – they eat things like sparrows and starlings, and yet as their populations declined and our habitats for opportunistic little birds increased, we seemed almost surprised at the explosion in the populations of these pesky birds. It seems that a common problem with human logic is to treat the symptom, not the cause of a problem. In this case we want to find a way to destroy the ever growing populations of invasive birds rather than try to pinpoint what it is that is causing the explosion in growth and working from there.
What is even more interesting – to me at least – is the methods in which we have tried to “deal with” these birds. We have done things from creating poisonous perches that will kill starlings to putting out statues of owls to keep the pigeons away. Perhaps a few sharp shinned hawks would provide just as much assistance, send a clearer message, and also not threaten to poison the water and other unintended creatures?
Another interesting idea is to try to figure out a way to co-exist with them peacefully or, if possibly, figure out a way to create a mutually beneficial relationship with the animals in a way that makes them an asset, not pests.
Take for example the purple martin and Griggsville, Illinois.
I discovered Griggsville by accident. We drive through the town each time Brett and I go visit his family in Peoria. It is a tiny little town, no more than a few thousand people, but yet it is very unique. The first time we drove through, I noticed all the purple street signs and these strange purple bird houses everywhere - there was even this crazy pole with tons of birdhouses climbing all the way up it. I recall asking Brett about it and him saying that they were to attract purple martins.
Purple martins, in my opinion, are not the most attractive birds there are, though they are a pretty color. But they do provide a very good service – they eat mosquitoes. They eat vast quantities of mosquitoes, upwards of 2,000 a day. The good folks of Griggsville noticed the service and joyfully encouraged them to roost.
Purple martins are not particularly adept home builders, so these large bird apartments (there are often multiple “quarters” in each house) provided an invaluable service by freeing the bird from having to figure out how to shelter itself, and during the muggy, hot, cookout times of the year, these purple martins keep the town from drenching themselves in pesticides. I like their idea of pest control!
Obviously, this tactic in itself is not be feasible for all manner of bird pests, for one purple martins were never a pest, they were actually endangered for a time. But they provide a unique example of symbiosis - rather than try to eradicate the birds, we could attempt to build a mutually beneficial relationship with them. Certainly we could begin thinking along these lines, or those such as reintroducing native predatory birds and leaving the rest of the work to nature.
One thing some naturalists and environmentalists often forget when they wax poetic on "the way nature used to be" is that our climate, the very topography of the earth (DC was once a swamp remember), our landscape have all changed so much that there is no going back. Who is to say that those previously “native” creatures would be able to thrive in the current environment? We would have to rethink our whole means of housing ourselves and structuring the land, but it is too little too late for that. You can’t go back – we have to remember that. And I have a real problem with people thinking that we not only can, but that we should try to control nature, as if we have the wherewithal to know how to restore that which we destroyed. Perhaps what would be best would be to leave it alone. An ecosystem is that which can sustain itself – a system that requires constant weeding, fertilizing, fussing, killing of “unwanted” plants and animals is by no means self sustaining, and is thus just yet another artificial creation of humans.
Just some things to think about.