Illegally dumped Koi and goldfish have invaded village water body
Walk the trail around Carpenter’s Pond and you will see numerous bright orange fish, or larger orange and white fish, swimming near the east end. Apparently, the pond has become home to numerous koi and, possibly, also goldfish that someone dumped in the pond.
The problem? Such unregulated fish stocking is illegal, and koi are an invasive species that can damage the pond’s ecosystem. More importantly — environmental experts say they are concerned these ornamental fish might find their way into Chittenango Creek or even Cazenovia Lake.
“I’d say we should be concerned about them being there and get rid of them ASAP,” said Thad Yorks, program director for the environmental biology and biology programs at Cazenovia College, who performs an annual fish survey of Cazenovia Lake. Yorks said his visual inspection of the pond showed him what appeared to be koi and probably goldfish in there, and there are certainly more in the water that can be seen from walking around the edge of the pond.
“Regarding impacts — they’ll compete with the native fish for resources like food and breeding habitat. Koi are just fancy versions of common carp; as such, they can/will get bigger and bigger and eat whatever they can fit in their mouths, so there would eventually be that direct impact on young, small fish of the natives. Then, if they are allowed to get old/large enough to breed, they’ll have that pond’s water all kinds of murky in mid-summer. And then there is the possibility that they brought along for the ride some pathogen like koi herpesvirus.”
Dave Lemon, state DEC fisheries manager for Region 7, agreed, calling the presence of koi in Carpenter’s Pond “problematic.” He said the DEC definitely does not want them somehow finding their way into Cazenovia Lake, which, according to DEC records, apparently does not contain carp at all.
“We would not want them to get into the lake,” Lemon said. “If there’s no outlet from the pond to the creek or the lake, it’s not as big a concern, but we certainly don’t want them getting out.”
Carpenter’s Pond, which is owned by the Cazenovia Preservation Foundation, outlets into the adjoining willow patch, which then runs into Chittenango Creek, according to CPF Conservation Manager Judy Gianforte.
It is “possible, but unlikely” the fish could get into the creek, Gianforte said, since they would have to travel through two grates and more than 1,000 feet of pipe to get into the willow patch, and then through another pipe that has a rapid drop down to the creek.
“With the discovery of the koi, CPF will cover the grate out of Carpenter’s Pond with a finer mesh to minimize the risk of the fish traveling further downstream,” Gianforte said.
So how did the koi and goldfish get introduced into the pond? Nobody knows, but all agree someone either got tired of taking care of them in their own pond and dumped them in Carpenter’s, or someone actually bought some fish specifically to “stock” Carpenter’s Pond.
“Either way, it’s illegal to put any fish in a body of water without a DEC permit and documentation that the fish are disease-free. But koi and goldfish are ‘regulated’ fish species that are illegal to put into natural bodies of water. Period,” Yorks said. “It’s disappointing that, at a point in time when so much effort has gone into public education about invasives and in a lake community generally so aware of the problems associated with invasive species, someone was ignorant and/or apathetic enough to do this. Even the pet stores for some time have been putting out the word that fish buyers should never release the fish into a natural environment.”
Cazenovia Deputy Mayor Amy Mann said she is also concerned about the introduction of these invasive fish into the pond.
“While it may seem like a novelty to have a giant goldfish bowl in Carpenter’s Pond, introducing invasive animal or plant species such as the contents of unwanted fishtanks into natural waterbodies is not only illegal but can have huge unintended consequences to the environment,” Mann said . “Eurasian Watermilfoil started as a common fishtank plant and obviously became a huge threat to waterbodies. As for the koi, I would like to explore whether they are truly contained within the pond, or whether there is any chance they could enter the creek system, and then seek an appropriate response.”
Yorks and Lemon both said the removal of the koi and goldfish could be as straightforward as netting them — their bright colors do make them easy to see — but other possibilities would be to drain the pond completely or applying a non-selective piscicide to the pond and eradicating every living fish in it and then restocking the native fish.
Both experts, however, do not think such drastic measures as draining and eradication or necessary. Yorks said he has a backpack electrofishing unit he could use to temporarily stun and net the fish and remove them.
“The second rule of invasive species management is to eradicate as quickly as possible if possible,” Yorks said. “Rule number one being to prevent their introduction in the first place.”
