SOUTH DAKOTA STATE - South Dakota is experiencing a unique "biological surge." While the state continues to debate long-term management for prairie species like the Lesser Prairie Chicken, immediate threats from invasive mussels and a surprising rise in black bear activity are dominating the local landscape this month.From the Glacial Lakes to the Black Hills, here is what you need to know to stay safe this season.
1. Black Bear Alert: Unusual Northeastern Sightings
In a rare move for early spring, South Dakota Game, Fish and Parks (GFP) issued an official advisory in April 2026 following confirmed black bear sightings in the northeastern part of the state.
- The Incident: Multiple sightings were confirmed near Pelican Lake, just southwest of Watertown, during the week of April 13.
- The Danger: While black bears are more common in the Black Hills, these "wandering" bears in the northeast are likely young males looking for new territory. They are currently hungry after hibernation and are targeting backyard attractants.
- Action Plan: Residents in Codington and surrounding counties should take down bird feeders immediately and secure all garbage. If you see a bear, do not approach it; supervise pets and children closely while outdoors.
2. Zebra Mussels: The "Permanent" Infestation
A damning environmental report released on April 17, 2026, highlighted a critical failure in the management of aquatic invasive species (AIS). Zebra mussels have now spread to 32 water bodies in South Dakota, with five new detections recorded just this past season.
- The Crisis: Once established, South Dakota currently has no effective mitigation plan for zebra mussels. They are currently causing irreversible harm to local fisheries and infrastructure.
- The "Walleye" Risk: New studies show that zebra mussels in South Dakota lakes are increasing the concentration of mercury in prized fish like walleye and perch.
- The Rule: "Clean, Drain, Dry." Before leaving any boat ramp, you must remove all drain plugs and ensure no water or vegetation is hitchhiking on your craft.
3. Emerald Ash Borer: The "ReLeaf" Program Launch
The City of Watertown officially launched its ReLeaf Program on April 6, 2026, as part of a massive recovery effort following the 2025 discovery of the Emerald Ash Borer (EAB) in the region.
- The Situation: EAB was confirmed in Ward D of Watertown last year. As of April 2026, the city is moving from detection to aggressive removal and replanting.
- The Incentive: Starting April 24, 2026, residents can receive up to a $100 reimbursement for planting an approved non-ash tree on their property.
- Action: If you have an ash tree on your private property, April is your final window to hire a licensed arborist for preventative treatment (typically done May–August). If the tree is already showing "woodpecker blonding" or D-shaped exit holes, removal is the only safe option.
4. Rattlesnakes: The "Garage and Shed" Phase
As of mid-April 2026, rattlesnakes are officially emerging from their winter dens across the western river breaks and the Black Hills.
- The Behavior: Because nights are still cool, snakes are seeking "thermal cover." This month, they are frequently found inside garages, sheds, and crawl spaces where they have been overwintering.
- The "Male" Circle: Biologists warn that the snakes most likely to be encountered right now are males making wide circles around their dens in search of food and mates. These active males are often more "quick to rattle" when surprised.
- Safety Tip: Before reaching into a dark corner of your shed or moving a storage bin this spring, use a flashlight and a long stick to check for "coiled" guests.
5. Ticks and "Snowmelt" Mosquitoes
Despite a "rollercoaster" spring with fluctuating temperatures, South Dakota is seeing an early start to the biting insect season.
- Tick Surge: The first deer tick of the 2026 season was recorded in the region on March 9th.
- The Nymph Warning: Experts warn that nymphal ticks—the size of a poppy seed—are at their peak right now. They carry a significantly higher risk of transmitting Lyme disease because they are so difficult to detect on the skin.
- Mosquito Update: While the "summer floodwater" mosquitoes are still weeks away, "snowmelt" mosquitoes are currently hatching in vernal pools and river bottoms.
- Action: Perform a "full-body scan" every night after hiking or gardening. If you live near standing water, tip it over every 5 days to kill larvae before they emerge.
Checklist for South Dakota Residents
- Secure Your Trash: Specifically in the Watertown/Pelican Lake area, stop attracting wandering bears.
- Inspect Your Ash Trees: Check for "blonding" bark and plan for treatment or removal before the mid-May EAB emergence.
- Clean Your Boat: Do not be the person who introduces zebra mussels to a "clean" lake like Lake Oahe.
- Wear Orange: Mushroom hunters heading into the woods this month should make themselves visible to spring turkey hunters.