BY GENE BULLOCK
Ospreys are thriving in Kitsap County. And nobody is happier about it than our local great blue herons.
As eagles multiply and fish stocks decline, eagles have shifted their diet to other birds. Pairs of eagles have learned to coordinate their attacks on waterfowl and nesting birds. While one adult lures an adult heron into a defensive attack, the eagle’s mate swoops in and grabs one of the young. Eagles have wiped out entire heron rookeries.
Great blue herons are still abundant, but they’ve been forced to adapt to this growing threat. One tactic is to seek secluded nesting sites, and abandon exposed rookeries. The other tactic is to nest in the vicinity of ospreys, which have little patience with marauding eagles, and are agile and aggressive enough to make even the boldest eagle think twice about provoking them.
Osprey nests are protected by law. This is especially good news for the herons, but can be a headache for the crews maintaining the cell towers, playing-field light towers and power transmission poles that have become nesting sites for a growing number of ospreys. Ospreys nesting next to power lines and transformers are occasionally electrocuted, sometimes resulting in power failures and costly problems for the linesmen responsible for fixing them.
Fish are a favorite food source for ospreys, herons and eagles, so conflict is unavoidable. In many states, people befriend local ospreys and help prevent power failures and related hazards by erecting separate poles with nesting platforms. These platforms sometimes become community projects to support wildlife and minimize conflict.
Partnering for mutual protection is not unique to ospreys and great blue herons. During the winter, many species of birds travel in mixed flocks. All benefit because some species are better at finding food and other species are better at sounding the alarm when predators approach.
On Machias Seal Island, off the coast of Maine, Atlantic puffins nest in close proximity to Arctic terns for protection. The puffin’s No. 1 enemy is gulls that prey on their eggs and young. Until cities and towns took steps to clean up the problem, open garbage dumps caused gull populations to soar. As a result, puffin colonies and other species of nesting birds were decimated by gulls.
Puffin parents fly long distances out to sea to find fish and bring them back to their nestlings. Feeding hungry young puffins is a big job, requiring both parents to spend long periods at sea, leaving their young vulnerable and unprotected.
Arctic terns congregate in busy nesting colonies with lots of activity. Although they are one of the smaller terns, these birds aggressively attack all invaders. Resident wildlife biologists wear hard hats and carry sticks, and still bear head wounds from these attacks. The stick is not a weapon. It is held above the head so the tern will attack the stick instead of the scalp.
Many believe our earliest relationship with dogs began as a similar pact. Early hunters allowed dogs to feast on the remains of their kills. The dogs, in turn, warned them of approaching danger and helped drive off other animals that threatened them. As the relationship evolved, they learned to hunt and work together.
Sometimes people wonder whether man domesticated the dog or if it was a mutual arrangement worked out over millennia. Either way, that bond has never been stronger than it is today.
— Gene Bullock is newsletter editor of the Kitsap County chapter of Audubon
