Lookout below: Underwater photography is window into fish habitat
Fish photos are arresting – and are windows into habitat.
Eric Engbretson clearly remembers the day he first donned mask, snorkel and fins to view fish underwater.
It was 1993. He was standing beside the 40-acre lake that ran into the woods behind his newly bought home. On this day, unlike all others, he decided to look into the lake rather than across it.
“So on a whim I went to town and purchased the best snorkeling equipment Kmart had to offer,” Engbretson recalled. “I got home. Geared up. Put my head under water and was astounded. I knew my next purchase would be an underwater camera.”
Today, Engbretson Underwater Photography of Florence, Wis., is the nation’s top supplier of photos of fish taken in their natural habitats. His photos appear in national fishing magazines, many government websites and publications and at Chicago’s Shedd Aquarium.
During the past 22 years, Engbretson also has evolved into an articulate spokesman and blogger for fish habitat conservation. He has shared his photos and underwater observations with stakeholders attending the annual Minnesota Department of Natural Resources roundtable. He has done the same with biologists attending the Midwest Fish and Wildlife Association annual conference.
“Most of my images are taken in water 15 feet deep or less,” said Engbretson. “Coincidentally, natural resource managers are intensely interested in this same depth because virtually every species of fish uses near shore areas during some portion of their life cycle.”
Paul Radomski, a DNR fisheries and aquatic vegetation biologist, focuses on Minnesota’s shorelines. His research from a decade ago suggests that between 1939 and 2003 about 25 percent of the lily pads, bulrush and other emergent plants disappeared from the state’s north-central lakes.
“No one was intentionally trying to destroy fish habitat,” Radomski said. “It simply became open space for boat channels, swimming areas and other recreational activities.” He said Engbretson’s images illustrate how fish use vegetation and other natural features for spawning sites, nursery areas, protective cover and more.
Engbretson sees the correlation of natural habitat and fish. In fact, when he arrives at a lake he has never photographed he looks for trees that have fallen in the water. “I can’t think of a fish that doesn’t like wood,” he said. “Unfortunately, all too often when a tree lands in a lake it soon becomes chain saw dust.”
What can anglers and others learn from Engbretson’s underwater photography? Said he:
Bulrush beds: They are buffet lines for fish. Insects inhabit the stems. Small fish feed on the emerging insects. Big fish feed on the small fish. Frogs are thickest in the near shore areas, where bass often lurk in exceptionally shallow water. “What’s cool about bulrush is that underwater insects use the stems as a ladder to climb up to the surface, and as they climb they get picked off.”
Lily pad beds: They provide shade and cover for bluegills, bass and other species. However, they often do not hold as many fish as many anglers imagine. That’s because lily pads have thin, stringy stems that don’t provide a lot of protective cover between the surface and bottom of the lake. Bulrush beds look like underwater forests; pure lily pad beds don’t. “However, bass do zero in on lily pad beds before the pads grow to the surface. These are good areas to target during the early season.”
Woody cover: The gnarly, old pine that tips into a lake is colonized immediately. The space between the branches provides excellent cover for fish. Wood that rises up to the surface is best because it provides a vertical element. “The neat thing about vertical wood is that you see fish stage at various heights based on water temperature. The difference may be only a degree or two but it makes a difference as to where the fish suspend in the water column.”
Aquatic plants in general: Fish relate to vegetation. Few are in the barrens, and those that are tend to be on the move because they know they are vulnerable to aerial predators. “Plants hold fish, keep soil in place, absorb the nutrients that would otherwise turn water green and they provide habitat for ducks and many other species. That’s why they are so valuable.”
Despite Engbretson’s advocacy for habitat, he chooses his words carefully. He is not a biologist. He knows his subjective observations are limited to the small number of lakes clear enough for his photography. “I am hesitant to make sweeping statements that are better left for biologists,” he said.
Martin Jennings, DNR aquatic habitat manager, is such a biologist. He concurred with Engbretson that habitat conservation in the littoral zone — water 15 feet deep or less — is important but stresses that conservation efforts above the water line are critical, too.
“Good fishing starts with good water quality,” said Jennings. “And good water quality starts with keeping soils and nutrients on the land rather than entering our lakes and flowing waters.” In central and northern Minnesota, he said sound forest management “at a scale that is meaningful” will be increasingly important for providing fish with the clear, well-oxygenated water they need.
“It would be a mistake to believe that simply dropping trees in a lake will sustain or improve fish numbers and quality,” he said. “However, combined shoreline and watershed conservation will get us a long way down that road.”
C.B. Bylander is a freelance writer from Baxter, Minn.
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