House Sparrows and Starlings Are Super Competitors
From: Steven Kroenke, Tallahassee, Florida
Date: 11/3/99
Time: 5:58:21 AM
Comments
Like it or not, house sparrows and starlings are super competitors. From small introduced flocks, they have spread like an avian plague across America and Canada, out competing many of our native hole nesting birds. The starling, in particular, has proven itself to be the master of nearly every native hole-nesting bird it confronts. How and why have such European imports been so successful?
Aggressive, persistent, well armed physically, and endowed with an unbelievable instinctive drive to procreate, they are formidable adversaries. The house sparrow is armed with a heavy, conical finch beak that can crush like a miniature vise. It is pointed and has a sharp cutting edge used to crack seeds and inflict damage on weaked bill birds like tree and cliff swallows and bluebirds. Swallows, in particular, have short bills with a wide gape. Their bills are relatively soft and rich in sensitive nerve endings. Such bills have limited crushing attributes and are no match in beak to beak confrontations with the vise-like grip of the house sparrow's bill. Purple martins, though swallows, are a different situation and can successfully defend their nests from house sparrows. The martin's larger size and very aggressive behavior will often prevail over house sparrows even though house sparrows have more powerful beaks. Sparrows may even confuse adult male martins with starlings and starlings are deadly enemies of sparrows, too! House sparrows adversely impact purple martin colonies by clogging houses/gourds with "martin-proof" nests. House sparrows build a typical weaver finch nest composed on a narrow tunnel entrance that leads to a nest chamber. Such a nest that is packed tightly in a house compartment or gourd will readily exclude the larger martin from entering many times. Sparrows, also, sneak into unguarded martin nests and destroy eggs and even kill newly hatch babies.
The starling is a virtual killing machine, an avian terminator. Armed with a dagger like beak, powerful long legs, sharp claws, and a muscular body, they are truly the super competitor. Purple martins, bluebirds, woodpeckers, house sparrows, and other hole nesting birds are no match for starlings. Some times, a determined flicker or other woodpecker will successfully defend its nest against starlings, but starlings usually reign supreme. Starlings will readily kill weaker birds, like purple martins, in ferocious battles inside the nest. The starling will grip the purple martin in its claws, hold the martin down, and savagely peck at the martin's head and eyes. Few martins can escape and will be killed.
But there is more to the success of house sparrows and starlings than just brute force and aggression. They "already" had the genetic knowledge and behavioral mechanisms for competition in place when they were first released in America over 100 years ago. Think about the following. In their "native" homelands of Europe and Asia, both house sparrows and starlings have been competing for thousands and thousands of years with other hole-nesting birds. And guess what? They have for the most part proven to be super competitors here, too! House sparrows out compete house martins and evict the weak billed martins from their mud domed nests. House martins are similar in size to tree and cliff swallows. But house sparrows are not so successful with the common swift which nests in holes. The common swift is somewhat similar to our purple martin in size. Interesting! Starlings out compete the European woodpeckers, like the green and spotted. The green woodpecker is similar to our flicker and the spotted is similar to our red-bellied and red-headed woodpeckers. Again, interesting comparison! So, it appears that house sparrows and starlings had thousands of years of successful competition in their native homelands of Europe and Asia. When they were introduced in America, they applied their powerful physical weapons, behavioral aggressiveness, and "genetic knowledge", to compete with similar American hole nesting birds. What worked with European house martins and woodpeckers for thousands of years also worked with American swallows and woodpeckers. House sparrows and starling, being super, and yes, "intelligent", competitors just did what was naturally programmed in the genes and continued their species in an incredibly successful manner.
We, as responsible purple martin landlords, must vigilantly eliminate both house sparrows and starlings from our martin colonies and not let these super competitors nest in our yards. They are highly destructive competitors and adversely impact our native hole nesting birds like purple martins, tree swallows, bluebirds and woodpeckers.
Steve Kroenke
