Bob McNamara splits his time between two worlds: the driest desert in America and the land of 10,000 lakes.
By winter, he’s a backcountry ranger in Death Valley National Park, and by summer, he’s a passionate defender of Minnesota’s waterways through University of Minnesota Extension’s Aquatic Invasive Species (AIS) Detectors program.
Water isn’t just a resource for McNamara. It’s life itself. Growing up in the Como Park neighborhood in St. Paul and playing near the water, he developed an early connection that became truly meaningful only after leaving. His revelation came during college in California’s desert, where the absence of water made him realize how deeply it was woven into his identity.
“You don’t know until it’s gone how important it is,” he reflects.
Picturing cleaner water
A photographer by trade, McNamara has become an invaluable volunteer in the AIS Detectors program. He regularly monitors water quality at Lake Vermilion and vigilantly searches for aquatic invasive species.
His photography background has proven especially crucial. He has contributed to identification guides, capturing detailed images of invasive species like the rusty crayfish: “A waterproof identification book that shows how to identify plants and invasive species is such an important tool for identification.”
McNamara is motivated to do this work because he loves Lake Vermilion, and he feels a profound urgency to protect it from invasive species.
“Relatively speaking, my home lake of Vermilion is pretty clean. With all the boat launches we have, there are many points where a new infestation of invasive species could occur. It’s crucial to survey those points on a regular basis because if we catch it in the early stages, we can stop it.”
Facing the challenges
McNamara spends his time sampling water, consulting with other aquatic invasive species monitors on Lake Vermilion, and educating boaters about their crucial role in keeping lakes clean.
The challenges are significant. McNamara has witnessed entire weed beds disappear within weeks due to aggressive species. His primary concern is the rusty crayfish, which he describes as moving into areas “very aggressively and chasing the native ones away.”
Yet, he remains optimistic about prevention. “In this type of work, one ounce of prevention isn’t worth just a pound of cure. It’s worth 1,000 pounds of cure.”
McNamara understands that Minnesota’s waters are more than environmental resources. They’re economic lifelines.
“People who live in Minnesota often take our water for granted – we have so much of it, and it’s of such good quality. Let’s keep it that way,” says McNamara. “What I want people to understand is how much of an economic engine the waters of Minnesota really are. Fishing, recreating, and canoeing are so important to the character and economy of our state. Our water quality isn’t just something worth saving from the ecological perspective.”
The duality of his experiences — alternating between Death Valley and Minnesota — gives McNamara a unique perspective. “I appreciate the two different worlds that I get to spend time in,” he notes. “I wouldn’t appreciate one as much without the other.”
Good eats: Bob McNamara’s invasive crayfish recipe
“If I had to pick one invasive species to focus on, it’s the rusty crayfish — because you can fight back by eating them!” McNamara says.
In fact, chefs from Louisiana prize Minnesota’s crayfish because the colder water up north helps them grow big and plump.
McNamara provides his method for protecting invasive species while enjoying a delicious meal.
- Catching: To attract invasive crayfish, use a minnow trap with chicken bones or fish guts in about 3 feet of water.
- Preparation:
- Soak the crayfish in saltwater or stun the crayfish by freezing them. Thaw before consuming (cook directly from frozen, or thaw in the refrigerator by placing the frozen crayfish package in a dish to catch any drips and cook within 1-3 days of thawing).
- Then, boil crayfish until they reach 145 degrees F internally.
- After cleaning and sanitizing your cooking environment, prepare a dipping sauce with sour cream and Cajun spices to serve with the crayfish.
- Eating tips:
- Crack open claws to suck the meat out.
- The best meat is in the tail.
- Expect small meat portions (thumb-sized).
- Plan on 10-15 crayfish per serving.
- Pairs well with: Cajun rice and a salad
If you have leftover cooked crayfish, store them in the refrigerator for 1 to 3 days. Reheat to 165 degrees F before eating.
Check out the Minnesota Fish Consumption Guide to find safe-eating guidelines for crayfish captured from lakes.
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