The Daily Bucket is a regular feature of the Backyard Science group. It is a place to note any observations you have made of the world around you. Snails, fish, insects, weather, meteorites, climate, birds and/or flowers. All are worthy additions to the bucket. Please let us know what is going on around you in a comment. Include, as close as is comfortable for you, where you are located.
May, 2013
Salish Sea
Pacific Northwest
Recently, during a lull in the rain, I had a chance to watch a Great Blue Heron (
Ardea herodius) feeding much closer than I'm usually able to...I think it's because I was in a kayak rather than on the beach. Herons are fairly common on the sandy beaches here, even right next to a road, and show no interest in cars or bicyclists. But if you stop, they are immediately on their guard, and will usually fly off. Brisk walkers are watched warily, but so long as you maintain a pace, they wait for you to go by, and then resume fishing. For some reason, this heron allowed me to drift quite nearby, but I stayed far enough away that he continued to fish.
Great Blue Heron has two principal fishing techniques. The first consists of standing motionless, its neck extended at an angle of about 45 degrees to the water surface. Only its head and eyes move to locate the prey. If no fish comes within range after a few minutes, the heron gradually moves a short distance away and takes up a similar position. When a potential meal comes close enough, the heron slowly folds its neck back and moves one leg in the direction of the prey. Suddenly, its entire body unbends, its head plunges into the water, it catches the prey in its bill, and it swallows it outside the water, using a deft movement of the head to drop the prey headfirst into its gullet.
Using the second technique, the heron slowly wades around in about 15-25 cm of water until it drives a fish out from its hiding place. The heron then stops and slowly stretches its neck.
When the prey is within range, the bird uncoils its body and thrusts its head into the water after it. After eating the catch, the heron resumes its walk. Should the bird fail to find sufficient fish in an area, it flies a short distance away and resumes fishing.
- Great Blue Heron Nature Reserve Society, Chilliwack, BC
This heron was using the second method. I couldn't catch his actual strike - too fast. After swallowing the fish, the heron shakes his head, ruffling and fluffing his beautiful neck feathers. They are always so elegant and graceful.
More Great Blue below the clump of seagrass.
While males and females are very similar, this one could be a male, with his long bill, almost twice the length of his head.
Great Blues are year-round residents in the Pacific Northwest, as they are in much of the country. I didn't see them on this beach for most of April. Perhaps they were feeding closer to their nest. I don't know where it is. I do know this is a favorite feeding beach for them though. Often there are several herons stationed fairly close to each other along the beach. Just offshore is an extensive eelgrass bed, calm and shallow, rich in small fish and crabs, providing plenty of prey for herons. At the end of the beach here, the herons were wading through masses of bright green sea lettuce surfacing in this very low tide.
One of these two flew off as I approached.
Can't report about nesting here, but elsewhere, nestcams follow the entire fascinating, and sometimes brutal, endeavor. In a woodsy area of Seattle, the
Washington state Dept of Fish and Wildlife has a nestcam operating. Unfortunately, this year's nest has been abandoned after repeated attacks by eagles. They report the eggs and young have been eaten by eagles and crows. It is possible the herons may start another brood. In the Pacific NW, heron eggs generally hatch in April or May.
However, the heron family has been more successful at the New York nest where Cornell has a nestcam. The first egg hatched two weeks ago and the nestlings are very active already. Two of the eggs have not yet hatched, so those heronlings will be smaller than their nest mates after they do. When food is scarce, not all the baby herons survive. The Cornell folks are hopeful about this family's chances.
Some more pics of this Salish Sea heron in Barlow Bay, wading and feeding in the shallows:
After a while I paddled away. He continued fishing. During the 15 minutes I watched him he made numerous successful strikes.
Most often I see herons standing on the shore or other hard surface, using the pure "waiting and striking" method. Here's a juvenile heron fishing from the dock, sitting on its heels to be able to reach down into the water, below the surface of the dock.
And this is a lovely sight, seeing one standing on a mass of seaweed, offshore. Bull kelp (
Nereocystis luetkeana) grows lushly in swift currents, anchored on rocky reefs in deep water. That's the Strait of Juan de Fuca and the Olympic Mountains behind it. Kelp beds are excellent fishing, and a thick tangled mass can easily support this 5 pound bird (surprisingly light, considering it's 4' tall). Many good fishing spots in the Salish Sea.
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What's happening in your backyard, as we move into June?