Back To Blog

Exotic Wildlife and Plants - OK to Enjoy, but Be Responsible!

  • By
  • Posted

The  popularity of having exotic plants and animals as pets is a trend that can potentially  put our native fish and wildlife habitats at risk. It is important for the  public to be aware that invasive fish and wildlife can disrupt the local  ecology and can out-compete native species. They should never be released.           Almost everyone  has found enjoyment in stopping to view a water garden or an aquarium at a  local restaurant or spa. There are local contractors that will come to your  home and install a peaceful, cascading waterfall that includes a pond liner,  pump and filter assembly. Many home improvement stores have ready-made kits for  you to install on your own.  These water  gardens add a very relaxing and aesthetically pleasing landscaping touch to a  home or business. We have a lovely "Planting for Wildlife"  habitat/pond area at the entrance to the Fish and Game Department in  Concord.  It's important to note that our  water garden does not include any invasive fish (in fact there are no fish at  all in it) or invasive plants.           When you add  fish to water gardens, it's another story that can go like this: It's summer;  the temperatures are hot and all seems wonderful. But in a few months, the  temperature will be falling.  What will  people who have added fish to their water gardens do with these fish when the  season changes?  I hope they are planning  ahead and have an environmentally safe plan for holding those exotic fish and  plants through the winter?  In many  cases, not having a plan or the logistics to store these fish appropriately  leads to a problem.  Understandably,  people become emotionally attached to these "pets."  If they cannot find alternatives to maintain  them, euthanization is unthinkable.  Many  times, these fish are released into local fire ponds at housing developments or  city parks.  Or worse, into local ponds  and streams!  This irresponsible action  can have devastating results, because some of these exotic fish or ornamental  plants and animals that people enjoy looking at in their aquariums or water  gardens have become aquatic nuisance species problems, disrupting the native  plant and animal communities. Invasive wildlife can disrupt the local ecology  and can out-compete native species due to higher tolerance to poor water  quality and/or high reproductive rates.         Another  scenario: Most families I know have at some point enjoyed an aquarium for pet  fish.  It is easy to understand the  popularity of this practice, because of the peace, tranquility and relaxation  that they provide. Many parents use aquarium fish to teach their children the  responsibility of pet ownership prior to purchasing a dog or cat. But what  happens to these exotic fish when once-responsible owners, with good  intentions, no longer have the interest in caring for them?  When circumstances change and someone is  forced to move to a new location where having these pets is not an option,  where do these fish end up?

Just recently,  I received a call about a fish kill at White's Park Pond in Concord.  Having grown up in Concord myself, I knew  exactly what pond the park manager was referring to.  In fact, I remember visiting this very pond on my bicycle to  enjoy these fish myself.  When exactly? I  won't tell, to prevent from revealing my age! When I arrived at scene of the  recent incident, I observed what I anticipated.   A shallow pond with an unusually high number of (overpopulated with)  goldfish, koi and bluegill, crowding the perimeter of the pond guarding  spawning nests.  Having enjoyed the  White's Park Pond fish experience in the past, I was saddened to see what was  happening.

My  professional career has blessed me enough to allow me to work with fish every  day.  I chose this career because I  believe in conservation of New Hampshire fish and wildlife resources. Years  ago, I never would have put much thought into how these fish may have gotten  there, and certainly wasn't aware of the risk these fish were presenting. But  the fact is, many of these exotic species are present due to the acts of people  with big hearts, good intentions or people who are simply unaware of the damage  it can cause. As a long time dog and aquarium owner myself, I would never  condemn anyone for loving their pets. Unfortunately, there is no shelter for fish  to reside until adoption, if the original owner can no longer care for them.

Koi and  goldfish are exotic species that must not get into state waters.  One reason is that koi and goldfish can  present a health risk to native fish species. Ornamental fish raised in  captivity have developed resistance to certain diseases, due to the typically  stress free environment of an artificial setting. Koi and goldfish that appear  healthy can be carriers of pathogens such as Koi Herpes Virus (KHV) and Spring  Viremia of Carp Virus (SVCv). SVCv, in particular, can cause serious problems  in wild baitfish populations. Many of our wild and native fishes have never  been exposed to some of these emerging pathogens. Therefore, many of our wild  fishes have never had the opportunity to develop an immune resistance to these  potential diseases. This is why all baitfish and fish being imported for  aquaculture must pass a pathological inspection prior to an import being  approved.

The New  Hampshire Fish and Game Department, by Administrative Rules, lists all  ornamental or aquarium fish as "non-controlled" provided they remain in a  "closed system." These same rules prohibit the release of any fish and wildlife  without a permit so to do.  Some other  states, Maine, for example, prohibit the possession of koi completely. Please  help us protect the natural resources of New Hampshire by being conscious of  the fact that those plants and animals you enjoy in your water garden or  aquarium are illegal to release into the wild, where they threaten native  wildlife.         For more  information on disposing of unwanted aquarium and pond plants and animals,  visit   By Jason M. Smith,   Chief, Inland Fisheries Division, N.H. Fish and Game Department

Add Comment

Comments are moderated. Please be patient if your comment does not appear immediately. Thank you.

This site is protected by reCAPTCHA and the Google Privacy Policy and Terms of Service apply.


  1. No comments. Be the first to comment.