Nature: Crafty herring gull impresses with problem-solving skills

 

Nature: Crafty herring gull impresses with problem-solving skills

A point of avian trivia: Only one state eclipses Ohio in the number of gull species seen within its boundaries. It is California, which dwarfs Ohio in size and has 840 miles of Pacific coastline. Twenty-seven gull species have been recorded in the Golden State.

Ohio lags California by only six species, with 21 gulls so far recorded. That gap will soon narrow, once new records of common gull (a European vagrant) and glaucous-winged gull (from the West Coast) are formally accepted. These vagrants were found in late December and early January on the Cuyahoga River in Cleveland – one of North America’s great gull hotspots.

The default gull in Ohio is the ring-billed gull. This is the species that roosts in mall parking lots, forms flocks on the Scioto River and local reservoirs, and scavenges scraps in McDonald’s parking lots. Occasionally, noticeably larger birds intermingle with the flocks. These are herring gulls, another common gull in Ohio, especially along Lake Erie.

Gulls are intelligent, long-lived, highly adaptable, and situationally aware, with a penchant for doing interesting things. Perhaps no gull out-gulls the herring gull. The big birds are well-known for their cleverness, and ability to solve problems.

As herring gulls spend most of their lives around water, they routinely encounter mussels. Mussels, or clams, are hard-shelled bivalves and - when sealed up - are, in essence, living rocks. It would require a hammer to crack most of them open. The reward for doing so? The meaty animal inside, a gull delicacy if there ever was one.

Clam-cracking is a true problem if you are a herring gull with no hands, hammers, or chisels. But somewhere along the line, the gulls learned about succulent protein and vitamin-rich clam meat and devised a clever trick to open clams.

On a recent trip to Edwin Forsythe National Wildlife Refuge, in the shadow of Atlantic City, New Jersey, I had the opportunity to photo-document herring gulls opening blue mussels. These bivalves are common in Reeds Bay on the south side of the refuge.

Ages before Isaac Newton watched an apple fall from a tree, leading to his “discovery” of gravity, herring gulls had learned to put gravitational pull to work. Hungry gulls would fly out to Reeds Bay, locate a blue mussel bed, and pluck a clam from its watery home. The hunter would then fly back to a refuge road of hard-packed gravel, and hover over it. From a height of several stories, the gull would drop the mussel like a feathered B-24 delivering a bivalve bomb.

The hapless clam would freefall toward an explosive doom, the gull flutter-dropping after it. Upon impact with the roadbed, the hard shell would shatter to smithereens and the gull would quickly seize the now-available meaty morsel. Speed was critical on the part of the hunter, as other clever but perhaps lazier gulls lurked nearby, ready to usurp the hard-won handiwork of the legitimate heir.

I’ve seen such tactics used by herring gulls numerous times in many places, including along Lake Erie. Many other gull species do this as well, including our common ring-billed gull. While this experience is, I’m sure, not fun for the clam, it is interesting to watch.

The oldest known herring gull lived to age 49, but we know little about gull longevity. As the global population is around a million birds, there are certainly older individuals, possibly even centenarians. An old clam-cracking gull has probably flexed a lot of mussels in its time.

Naturalist Jim McCormac writes a column for The Dispatch on the first, third and fifth Sundays of the month. He also writes about nature at jimmccormac.blogspot.com.