SIGN OF SPRING: Frogs croaking and peeping in Hauser Pond. Pike in Big Creek, Sapsuckers and Kinglets!
Crossroads at Big Creek is locally renowned for its Sucker Run, but the spawn of Northern Pike, while not as frenetic, is just as interesting and it’s underway! Researchers from the DNR and UW-GB have confirmed it.
When do the adult fish swim through The Cove and into Big Creek? Like spring weather, the date varies from year to year. Researchers currently believe that day length and warmth trigger the annual breeding event, with a water temperature of 36-40 degrees being the preferred range.
In the fascinating article “Life of a Pike” ( in the Young Naturalist section of Minnesota Conservation Volunteer published by the MN DNR) Scott Moeller wrote: “Imagine that you are a northern pike at the beginning of your life cycle. You enter the world as an egg about the size of a candy sprinkle. You are stuck to the leaf of an underwater plant in a shallow wetland. It is here that your parents scattered you and about 50,000 of your brothers and sisters. (Talk about sibling rivalry.) Your parents chose this spot for your nursery very carefully.The shallow water warms easily in the sun. Because fish are cold-blooded, warm water will help you and your siblings grow and develop as quickly as possible.
“You develop inside your tiny egg for about two weeks, all the time in danger of being discovered by a fish, turtle, or other predator. After hatching from your soft eggshell, you remain stuck to an aquatic plant by a sticky patch on your forehead for the next 10 days. You are now known as a “sac fry.”
Sac fry don’t look much like adult pike. No more than 9 mm long, they don’t have fins or even mouths. Actually, sac fry look more like tadpoles than fish. They are called sac fry because their egg yolks are inside their pudgy bodies. They develop quickly by absorbing the contents of the yolk. How fast this happens depends on the warmth of the water, usually between three and tens days.
Once the internal food is gone, the developing pike , which at this stage are called a “swim up fry, ” starts hunting for food, starting a lifetime of voracious eating. At first, fry just eat tiny plankton and making short swimming trip to the surface to eat and then returning to their grassy hiding places.
It’s unlikely the Crossroads visitors will actually see the fry, but the creek is very low this year, so chances of seeing the large females and somewhat smaller male northerns are better than usual.
Visitors are always welcome to use the trails, but a naturalist led hike is scheduled for Sunday, April 12, at 1:00.
Speaking of Friends, their April meeting is scheduled for Tuesday, April 14, at 6:00. Anyone wishing to get involved in volunteer efforts at Crossroads is encouraged to attend.
This weekend, Crossroads is hosting a continuing education for class for teachers call Teaching Wisconsin Wildlife. For more information and to enroll, visit http://www.uwgb.edu/educationoutreach