FORT WORTH, Texas — Editor's note: The video above is a report on the colony from early August.
At least 34 of the 40 nutria living at a park in Fort Worth have been euthanized, according to a report from city officials.
The swamp rats are considered "an exotic invasive species," officials said.
The colony was first reported at Krauss Baker Park in early August.
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According to state wildlife officials, nutria can be an issue because they multiply quickly and eat a lot.
Nutria enjoy plants and can eat up to three pounds a day, said Rachel Richter, a wildlife biologist for Texas Parks and Wildlife. Female nutria can have two to three litters a year, of up to 15 offspring.
They are also a problem in California and Louisiana.
The nutria had congregated in the Fort Worth park partially because local residents were feeding them, officials said.
The city will continue it's efforts to reduce the population to a reasonable level, according to city officials.