Stocking Sanity—Some Wisdom From A Pro
Trout stocking is the lifeblood for both spin fishers and fly anglers alike. It provides recreational and educational outlets, as well as opportunities to harvest for those that desire to catch and keep.
As the owner of a fly fishing guide service, I rely in good proportion on the stocking programs in and around my local area. Stocked rivers serve as staple locations for learning, allowing anglers great access to areas where both size and numbers are present throughout the year.
With trout stocking being of vital importance to the angling communities, AND the number of anglers increasing significantly due to COVID–we thought it would be a good time to have a well-balanced look at trout stocking in general.
Commonly known big picture concerns when planting trout are
- Stockers preying on and/or competing with native populations for food and habitat
- The introduction of disease
- Planted fish altering the ecosystem to the detriment of native species
We sat down with Fisheries Biologist, Lee Simard to help provide scientific responses to topics like catch and release vs catch and keep, stocking vs. sustainable reproduction, as well as to nail down some big picture thoughts on trout stocking in general.
Lee Simard is a Fisheries Biologist with the Vermont Fish and Wildlife Department. He received a B.S. in Environmental Sciences and M.Sc. in Natural Resources from the University of Vermont. In his current position, he helps to manage and protect a diverse range of fisheries for Vermonters including wild and stocked trout, walleye, panfish, landlocked Atlantic salmon, and state endangered lake sturgeon.
The pro’s and con’s of trout stocking can certainly be balanced by ensuring stocking is conducted appropriately. Most trout stocking in Vermont is conducted to provide recreational fishing opportunities, thus stocking is limited to areas where wild populations do not exist or are insufficient to meet high fishing pressure. — Lee Simard
Interview Q & A
As a fisheries biologist, can you provide your big-picture thoughts on Vermont’s stocking programs?
Vermont’s stocking program is a very effective management tool for increasing recreational fishing opportunities for anglers throughout the state and, in some cases, working toward restoring extirpated populations. Stocking is focused in areas where adequate wild populations cannot be sustained due to physical or environmental habitat limitations.
Stocking programs are expensive and do have the potential to have ecological impacts if implemented inappropriately. However, the benefits of these programs can justify the costs and impacts can be minimized provided the program is managed effectively to meet specific fisheries management objectives.
What are the solutions that help balance out any pros and cons of trout stocking?
The pros and cons of trout stocking can certainly be balanced by ensuring stocking is conducted appropriately. Most trout stocking in Vermont is conducted to provide recreational fishing opportunities, thus stocking is limited to areas where wild populations do not exist or are insufficient to meet high fishing pressure. By limiting stocking to these locations, many potential impacts to wild trout populations are reduced including the potential for displacement, genetic introgression, or direct mortality.
In Vermont, genetic impacts are further reduced by stocking only sterile, triploid brook trout which would be unable to reproduce even if they survived and migrated to areas with wild populations. Extensive disease testing is also conducted in hatcheries to limit the risk of transmitting diseases into new areas.
In Vermont, is the main purpose of stocking 1) recreation or 2) to replenish species in a chosen waterbody?
The purpose of nearly all of the trout stocking in Vermont is to provide recreational fishing opportunities. Extensive resources and staff time are focused on maintaining and improving wild trout populations in Vermont and the use of stocked trout is never considered an alternative to protection or restoration of suitable trout habitat.
We recognize though that some areas are simply no longer suitable for trout, usually due to extensive land use and habitat changes that cannot feasibly be restored. Thus, in these instances, stocking provides anglers an opportunity to fish these areas, many of which are located in more developed and accessible locations.
In a few instances, stocked trout, landlocked Atlantic salmon, or lake trout are being used to attempt to restore wild populations to waterbody, but these are very explicit efforts that are typically part of a much larger restoration and management program.
…given most stocked waters in Vermont are put-and-take fisheries where the stocked trout is not expected to survive past the summer, it’s important to remember that a released stocked trout is not going to contribute to the long-term maintenance of the fishery, but rather will only be around for a few additional weeks or months. — Lee Simard
What are the variables that go into deciding which waterways get stocked?
Stocking is conducted to provide recreational fishing opportunities, so the waterbodies that are stocked are those that do not already have wild fisheries and that receive sufficient fishing pressure to justify continued stocking.
If a waterbody already has wild trout or is a popular bass fishery, for example, stocking trout would likely be a poor use of resources as nature is already maintaining that fishery. Similarly, if a waterbody is stocked but is never targeted by anglers, stocking should be discontinued.
Can you comment on the mortality rate of stocked trout? Are trout likely to die if caught and released in an efficient manner or are they pretty hardy?
Stocked trout are assumed to be less likely to survive in the wild as compared to wild fish as they have not developed the same foraging and predator avoidance skills.
When caught, a stocked trout likely experience a similar level of fishing-related mortality as wild trout. If an angler is not intending to harvest a fish, we strongly recommend they always follow the best catch-and-release practices, regardless of whether the fish is stocked or wild.
Do you have an approx. holdover rate for stocked trout? Can the waters you stock can maintain trout year-round or does the water in the summer months get too warm for trout to survive?
Most of Vermont’s trout stocking are designated as “put-and-take” where we expect no survival to occur, especially in rivers and streams. Creel surveys have been conducted in many different rivers over the past 40 years with trout that were stocked and “marked” with a fin clip the previous year. Only a handful of trout with the previous year fin clip were observed throughout all of these creel surveys even after conducting thousands of angler interviews.
Similar results have been seen in other states as well. High water temperature is usually the limiting factor preventing the survival of stocked trout, but also prevents the survival of wild trout. If water temperature and other habitat factors allowed wild trout to be present, those fish would provide a wild fishery and would preclude the need for stocking.
Most lakes and ponds that are stocked are similar in that they do not have the appropriate habitat to allow trout to survive year-round and only provide put-and-take fisheries. However, some waterbodies do remain sufficiently cold and provide put-grow-and-take or “maintenance” fisheries where some holdover is expected. Anglers have the ability to catch larger trout in these waterbodies, but other habitat factors typically prevent successful reproduction and the fishery must be maintained through annual stocking.
How do you feel about catch and release? Does it simply buy a couple of weeks or months for catch and keep anglers to come in and harvest or is it helping to replenish a waterbody?
Provided they are following all appropriate regulations, it is up to the personal preference of an angler about whether they want to harvest a stocked trout or practice catch-and-release. However, given most stocked waters in Vermont are put-and-take fisheries where the stocked trout is not expected to survive past the summer, it is important to remember that a released stocked trout is not going to contribute to the long-term maintenance of the fishery, but rather will only be around for a few additional weeks or months.
When determining the number of trout stocked into a particular waterbody, our calculations assume fish that are caught will be harvested, so a quality fishery should remain even if they decide to take home a meal for themselves and their family.
Can holdover trout reproduce?
In Vermont, all stocked brook trout are triploid meaning they are sterile and unable to reproduce. Similarly, all rainbow trout stocked into rivers and streams, some of which may have wild rainbow trout populations, are also triploid to eliminate the possibility of reproduction.
It is possible for holdover brown trout or diploid rainbow trout put into lakes and ponds to reproduce; however, these waterbodies typically do not have suitable spawning habitats.
If spawning habitats were present, self-sustaining populations would likely already be present and would preclude the need for stocking in that location.
If the trout are stocked in areas with little to no wild populations, why not stock trout that can reproduce?
Areas that are stocked have little to no wild trout populations because the habitat conditions needed to support a population do not exist. In most cases, elevated water temperatures are the limiting factor. Thus, even if diploid brook trout that could reproduce were stocked into the area, they would not be able to survive either.
The intention of these put-and-take stockings is to provide a fishery in areas where they could not otherwise exist due to habitat limitations. Where the habitat does allow for trout populations to persist, we prioritize maintaining the existing wild populations rather than try to supplement that population with stocked trout.
How can the average angler help support your project(s)?
Anglers should get out and enjoy the stocked fisheries that their own state agency provides. I often hear anglers say that stocked fish are “good for kids to learn how to catch.” While I agree with this, I think they provide a great opportunity for experienced anglers to introduce fishing to adult-onset anglers as well. Stocked trout can also provide a fun opportunity for even the most experienced angler.
Stocked waterbodies are often conveniently located where people live, making them an easy location to squeeze in a quick fishing trip at the end of a day without having to travel a long distance. Although it may not be the same as hiking several miles to an untouched section of a stream, it’s surprising how often you’ll find an exciting piece of water hidden away in your own backyard that you wouldn’t have discovered if you just ignored the stocked fishery.
It was an absolute pleasure to talk with Lee and learn from his expertise and wisdom in relation to stocking programs. We are so, so grateful for his time!!
If you really wanted to geek out in your evening reading, here is a link to Vermont’s Trout Management Plan. Everything Lee discussed in this article is talked about in greater detail in the Cultured Trout section. It’s a great document that guides his work every day!
We hope this article was helpful and maybe added new perspectives on fish stocking programs in general. If you have additional questions or insight, please feel free to leave a comment below
All fish stocking images, as well as the bridge image above, are courtesy of MTSOfan