(pensive music) - [Meg] We all knew that live bait were really important in the state that a lot of live bait movement was happening.

But it pretty quickly became clear that no one really had a good handle on whether that was a risk for the spread of invasive species and fish pathogens.

(pensive music continues) - Well, it surprises some people to know that the release of unused bait after a fishing trip is illegal.

It has been for a long time and although there's on every fishing license and in the regulation books and signs at boat ramps, it tells you not to do it.

A lot of people still do.

- It's just funny, the number of people like would say, like, "Oh, I'm working on bait fish," "and, you know, releasing them," and the number of people that say, "Oh, I dump mine in the water all the time."

I think most people really just don't think about it and really don't know about the law or don't understand why it's a law, it's a pretty high number.

- We know there's lots of infectious agents in the bait supply, viruses, parasites, bacteria.

When that pathogen's introduced to something like a walleye or musky, it can kill that fish.

- I have grown up in Minnesota, I've been around the lakes and rivers my entire life and as a scientist, I'm fascinated by all of the diseases that are out there.

As an angler and as a resident, they're horrifying.

It's not fun to think about.

- About 10 years ago, a virus called viral hemorrhagic septicemia broke out in the Great Lakes.

Huge, massive fish kills, and one of the routes of transmission and spread in this region is through the bait supply.

(pensive music continues) There's also invasive species that can hitchhike in bait buckets in the same way they hitchhike and live wells or ballast water and boats.

And some of those invasive species like silver and big head carp look awfully like some of the shiner minnows that are just sort of bycatch from wild harvested baits.

- The majority of Minnesota bait fish are not raised in aquaculture settings or hatcheries.

Majority of Minnesota bait fish are harvested from wild sources, which are not typically subject to pathogen testing, biosecurity.

- Lots of little fish moving all over the landscape being introduced to new places introduces risk.

And our program here wanted to understand those risks and help managers develop strategies to address it - In order to reach a really large number of anglers and understand what's going on statewide, we elected to do a large scale statewide survey.

We did two surveys, and both of them were a mailed survey invitation.

So, for the first survey that was done based on a list of anglers randomly selected from the electronic licensing system, which is the database of all folks that purchased a fishing license in Minnesota.

(pensive music continues) In our first survey, the primary aim of this survey was to simply understand the behaviors that anglers are doing, understand the fish that they're purchasing, the species they typically go for, how many they typically buy, all of the behavior that goes into their fishing in a year.

- [Nick] There's just over a million licensed anglers in Minnesota and from our surveys we've determined that about 70% of them use live bait fish at least some of the time.

- The most popular species were fat head minnows, followed by several species of shiners and white suckers, as well, were extremely popular and folks tended to buy about two to three dozen fish, but, sometimes that number was much higher.

(bright music) The first survey was 4,000 selected from across the state and we received about a 20 to 25% response rate on that.

The second survey, we did 8,000, and we received a similar 22% response rate.

So about 1,700 surveys came back from the second survey.

In the second survey, we really focused on the why of their behavior, things about their attitudes and beliefs.

And what we saw largely there was that most anglers wanna do the right thing.

They're concerned about invasive species and they're interested in making a difference.

But we also found a lot of them lacked knowledge about invasive species' regulations, especially related to bait disposal.

In both surveys, we found about 20% of anglers that use live bait release it, or have released it at least once in the past year.

We found that a much lower number of folks say that they intend to release live bait.

The folks that think live bait fish release is the right thing, they most commonly reported believing that it was going to actually be a good thing for the ecosystem.

We also found that there were people who reported not wanting to make bait fish suffer in disposing it.

That was another reason why they didn't feel like they wanted to put it in the in the trash can.

But the overwhelming majority simply did not know the regulations.

When we control for that, when we eliminate the folks that say they don't know the regulations, the percentage of anglers that report releasing their live bait fish plummets to about 2%.

And so most anglers who know the right thing, do the right thing.

I think that messaging tailored to that idea could be really powerful.

Pointing to the fact that 80% of anglers in Minnesota do properly dispose of their live bait could be powerful.

Or telling folks about the rules and regulations in a way that focuses on the positives rather than on the negative enforcement or regulatory punishments associated with improper disposal could be really powerful because generally speaking, Minnesota anglers are not acting out of malice, but rather out of lack of awareness or knowledge.

I think next step would be looking at the messaging that DNR currently does around live bait fish and understand why that's not translating to knowledge among anglers.

I know that they have emphasized clean, drain, dry and dispose in the past, but I think a broader application of that message to the population could go a long way towards reducing live bait fish release.

Some counties have done this work where when you buy a bag of bait, there's a sticker or a message attached to it.

When you're right there at the lake, you're getting that reminder or that prompt of bait disposal regulations and recommendations.

If we can tell people what they need to know, when they need to know it, at the place they need to know it, that can be really powerful.

I think social media can play a really important role here because social media is increasingly the way that folks of younger generations learn about angling and learn about natural resources.

We did find that most younger anglers did not know about regulations and we're more likely to release live bait fish than older generations.

We do have an ongoing study looking at bait retailers.

A very important piece in the puzzle, a really.

- [Nick] We've had a great response from bait shop owners.

They want to be part of the solution and so they do a lot of work to sort of look in those tanks, identify things that aren't supposed to be there and pull it out.

But there's a lot of fish moving around and not everybody knows what to look for.

- There's almost nothing you can do at the point of sale to test for or treat pathogens.

It's really just about communicating with anglers at that point.

- As we think about the risks and the maybe risky behaviors, it's important that we weigh the benefits, too.

The bait fish industry is, there's hundreds of businesses that have license to harvest and grow bait fish, but a thousand retail locations that sell those bait, it's a multimillion dollar industry and it's supporting a multi-billion dollar recreational fishing industry.

I'm an angler.

I'm one of those 70% that like to use baits.

It's important to the culture here in Minnesota.