Great Barracuda - Sphyraena barracuda

Great Barracuda - Sphyraena barracuda

April 17, 2015

Migration

Image by Mike Laptew ©

The Earth is flush with many spectacular rituals and phenomena. Think: mass coral spawning, Northern lights, phosphorescence.

Migrations have always intrigued me. When a Rubythroat Hummingbird recently showed up at my front porch looking for the jar of nectar I keep hanging each summer, I thought: "Holy COW! That little bird came all the way from MEXICO and REMEMBERED how to get back to this very spot in VIRGINIA!" I quickly prepared a new batch of nectar, hung it on the porch, and sure enough, the little bird returned again.

Fish migrations are another source of wonder. Think about it: Salmonids hatch in rivers (sometimes miles upstream), move offshore, and return to the very same stream to spawn as adults. American Eels make the opposite migration.... adults spawn somewhere in the Sargasso Sea, and their offspring move inshore and upstream until maturity. Other fish migrations remain a mystery. To this day, no one knows for sure where Great White Sharks spawn, or really why they travel such long and seemingly random distances.

Shads (collectively called "River Herring") are anadromous and a vitally important link in the food web. They used to have unimpeded pathways to their spawning grounds. When the rivers they traveled were dammed, their numbers plummeted. Aside from the dams and natural predators, they also had to overcome pollution, siltation, water withdrawal, and over-fishing. Today, some of those dams have come down, and other dams have been modified to include fish ladders. It's been proven that once a dam comes down, the fishes return almost immediately! Amazing.... An internal GPS and a drive to reproduce is hard-wired into the fish's DNA and cannot be suppressed, even by a dam.
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The beautiful photo above was taken by Mike Laptew of Laptew Productions. His images document the gorgeous and often overlooked diversity of fresh and salt water wildlife, both above and below the surface. Take a look here to see more.

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