Cambrian: Opinion

August is a great time to observe ocean harvest off the Central Coast

If you live on the Central Coast and look at the ocean, you may have noticed quite a bit of activity out there.

News stories tell us about sharks, humpback whales and by-the-wind sailors (pelagic jellyfish). From the shore, we see fabulous flocks of seabirds plunging and diving into the sea, while fishing boats crisscross the horizon. The offshore kelp beds are so lush and thick that egrets and herons can literally stand on the kelp while they hunt for small fish and crabs.

Like seasons of harvest on land, the ocean also has periods of productivity. Those of us who live on the coast are fortunate to be able to watch the seasons of the sea. Some years are more productive than others, and this summer has turned out to be a good one for marine biodiversity and abundance.

Remember those windy days in May and June — the ones that set off the allergies and whistled around the corners of the house? Those sustained winds stirred up the ocean’s surface, creating upwelling currents that lifted deep, cold water, laden with nutrients, and dispersed them through the water column.

Those nutrients, along with the longer days of sunshine, were just what the kelp needed to grow, sometimes as much as 12 inches a day.

Less visible, but no less important, were the tiny planktonic plants and algae that flourished in the nutrient-rich waters. They proliferated during the long summer days, giving coastal waters a greenish tinge.

When plankton are abundant, small fish aren’t far behind. They form feeding schools that follow plankton blooms. These schools of small fish may be composed of sardines, anchovies, smelt or a combination of species. Collectively, they are referred to as bait fish, since they are the primary fish used by fishermen as bait for catching larger fish. Swarming schools of bait fish are called bait balls.

Bait balls attract pretty much every predator in the ocean food chain. Medium and large fish eat the little fish. Pelicans, cormorants and shearwaters dive for small and medium-sized fish. Whales, dolphins, seals and sea lions eat them all. This is when we see incredible “feeding frenzies,” where the marine life comes together to partake of the abundant food supply.

The productivity created by the windy spring months and long days of summer culminates in the ocean harvest season of August and September.

The ocean harvest season doesn’t last forever. The weather patterns will change, and the marine wildlife will move elsewhere.

Now is a good time to stake out a favorite spot on the coastline. Picnic dinner and beverage of choice are optional.

Enjoy the season!

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