Monday, May 1, 2017

The Algonquin Indians Called it "Musquash"

Muskrat, showing off the teeth and the fur that make them famous

It's about time to get enter a mammal into the discussion. The Common Muskrat (with special emphasis on Common) is aptly named in marsh country. While often mistaken for a miniature beaver, they are actually an adeptly aquatic freshwater rodent more closely related to mice and rats. At 15-28" long (including their markedly narrower tail), "rats" rarely exceed 4-5 pounds (compared to 20-70 lbs for their paddle-tailed cousins). Anyone who has encountered them at particularly close range can attest to a strong and distinct odor that literally fills your nostrils . . . and won't let go!

While seemingly small and innocuous (at least at a distance), muskrats are more than just pungent passers-by in a coastal marsh ecosystem.  They are intimately tied to the ebb and flow of cattail populations, driven historically by water level changes and more recently by an influx of invasive species like purple loosestrife and Phragmites. When cattail populations are strong, dense stands can support tremendous numbers of muskrats.

According to the ODNR, females normally produce up to five litters per year in Ohio, with each litter containing up to seven young. That’s up to 35 young a year from a single reproducing female! Juveniles are able to take care of themselves within a month and are on their own and often reproducing themselves by the following spring. With this dizzying math in mind, it's not outside the realm of possibility that local lore could be true: a neighbor of the marsh contends that in the 1920s and '30s as many as 10,000 muskrats were trapped off the Bay View marshes in a single season!

A free-standing muskrat lodge made out of cattails becomes a haven
for everything from nesting waterfowl to reptiles and amphibians
Muskrats are deeply intertwined with the natural and human history of marsh country. Like commercial fishing, trapping has been a mainstay for generations along Lake Erie -- and muskrats have been a foundational and consistent resource. While fur prices continue to yo-yo, trappers persist not only to supply domestic and international demand (now largely from Russia and China), but also to help prevent these tireless tunnelers from making Swiss cheese out of the earthen dikes and levees that help sustain their aquatic habitats.

In the last two weeks alone, we have repaired more than a half dozen subsurface "runs" that have caused breaches within internal dikes. This management challenge tends to come in waves, particularly when water levels are altered in areas that have not dramatically changed in recent history. By drawing water off a unit that has been held high for multiple years, we are exposing internal cavities that can quickly become breaches under changing water pressure. As with everything on the marsh, change begets change.