Feral cats make invasive species list

  • Dennis Fujimoto / The Garden Island

    A cat leaves the refuse disposal container Saturday morning following its forage for food at the Ahukini State Recreational Pier parking lot.

  • Dennis Fujimoto / The Garden Island

    A cat looks for handouts, along with chickens, Saturday morning at the Ahukini State Recreational Pier parking lot.

LIHUE — Feral cats have been added to Hawaii’s list of most impactful invasive species, and advocates of trap-neuter-release (TNR) say the state should reconsider.

Feral cats were among little fire ants, rapid ohia death, pigs and other species on a list of some of the most impactful invasive species in Hawaii, submitted to the Western Governors’ Association by Gov. David Ige.

Hawaii’s list was added to those of the rest of the Western states, and those species were distilled into the Top 50 Invasive Species in the West list, released last week.

“Feral cats are a non- native species that is known to cause harm in natural resources, including terrestrial and aquatic wildlife,” said Cindy McMillian, communications director for the Governor’s Office.

She continued: “Parasites carried by cats also present human health concerns.”

Feral cats are avid hunters of Hawaii’s native wildlife and eat native birds and insects, including the endangered Hawaiian petrels, Newell’s shearwaters and Koloa ducks.

Cats carry toxoplasma gondii, which is a parasite that can impact birds and mammals, and the species is the principle threat to 8 percent of critically endangered birds, mammals and reptiles, according to the Hawaii Invasive Species Council.

Pet cats are not included under the listing, but TNR cats — also known as community cats — are.

Basil Scott of Kauai Community Cat Project (KCCP), which operates a TNR program on the island, says TNR cats should not be included on the list, and the current listing should contain a distinction between feral mountain cats and feral urban cats.

The cats within KCCP’s TNR program don’t target the same species that feral mountain cats do, Scott said, and many times they are far less dangerous and more tame than “truly feral cats.”

“We do TNR in our communities, not in wild areas containing sensitive species’ habitat,” Scott said.

KCCP has done TNR on 5,400 cats in the past decade and reduced the community cat population by 18 percent, or 2,200 cats, according to Scott.

He pointed out that trapping and euthanizing 23,000 cats during that same time reduced the community cat population by 10 percent.

That percentage has been calculated by taking the total euthanasia numbers of feral cats documented over the past decade in Kauai, subtracting the number of cats adopted from the number of cats surrendered.

“Even if you hate the cats, TNR is helping more than traditional methods,” Scott said. “That’s why that reference should not be on the governors’ list.”

Feral cats landed at No. 13 out of the top 25 invasive terrestrial species in the West. Feral hogs were listed as No. 6, coqui frogs were No. 19, and little fire ants came in at No. 25.

The terrestrial invasive species list submitted by Ige to the WGA is Hawaii-specific and includes rapid ohia death, miconia, mosquitoes, rats, albizia, goats, deer, coconut rhinocerous beetle, strawberry guava, Hawaiian ginger and snails on Hawaii’s terrestrial invasive species list.

None of Hawaii’s invasive aquatic species made it on the WGA’s top 25 list. However, Ige submitted 15 species for consideration: mangrove, giant salvinia, rice noodle bryozoan, buffalo grass, gorilla ogo, armored catfish, tilapia, hookweed, apple snails, upside-down jellyfish, Australian mullet, pickleweed, leather mudweed, prickly seaweed and Asiatic clam.

“The rankings produced by the WGA reflect submissions from across the West, including some that we share with others states and some that are currently found only in Hawaii,” McMillian said.

Ige chose to be part of the WGA initiative, which provides the first list of its kind for the West Coast states, as a way to help strengthen Hawaii’s biosecurity efforts.

“Strengthening our biosecurity protocols at ports of entry with our partners on the continental United States through the Western Governors’ Association allows us to take further steps to protect our precious natural environment,” Ige said in a statement to TGI about the WGA list.

He continued: “Protecting our environment is vital to our state’s economy and livelihood of all Hawaii’s people.”


Jessica Else is the environment reporter at The Garden Island. She can be reached at jelse@thegardenisland.com.

  1. Steven McMacken March 18, 2018 5:31 am Reply

    People are finally waking up. Well, some are.

    I think The Garden Island is doing a disservice to the community when they include erroneous statements from people like Basil Scott of KCCP. Mr. Scott has shown himself to be blind to the fact that trapping and releasing feral cats does absolutely nothing to help protect the native species on Kauai. He has convinced himself and some others that his methods work, when, in fact, they do not.

    He proudly says that his organization euthanized 2,300 cats a year over the past decade. Out of a feral population of more than 230,000, that’s a pittance. The feral cat population is INCREASING at a rate that far exceeds the rate at which they are being killed! Even if the feral cat population were to remain constant, it would still take 100 YEARS to eliminate them all . . . 100 years! Unfortunately, by then the feral cats would have had plenty of time to kill off any remaining endangered birds or other endangered species on Kauai.

    It’s time for the Kauai Community Cat Project to shut down its TNR program and start EUTHANIZING feral cats.

    1. Hope A.Duchainel.p.in March 18, 2018 9:23 pm Reply

      I am horrified that the Hawaiian government would allow these poor cats to be euthanize. Why doesn’t the government enforce the spay or neuter law?
      Hawaii is already in danger with their volcanoes. The answer is not euthanization, but proper maintainable action. I am an animal advocate and I am totally against this practice..

      1. Jamie Moore March 19, 2018 3:01 pm Reply

        I would like to point out (1) that humans have created the feral cat problem by not neutering or keeping indoors pet cats and therefore humans need to find a humane way to deal with the problem and (2) that humans have contributed to the destruction of native wildlife by, among other things, habitat destruction. Cats are domestic animals, not a non-native wildlife species and as such should not be classified as an invasive species.

        1. Nainoa March 19, 2018 7:52 pm Reply

          Cats may be a domesticated species but they come from wild beginnings. As a result they are very capable of colonizing wild places and acting like a wild predatory animal. They have spread through every habitat type in the Hawaiian islands from coastal beaches and wetlands to alpine habitat on Mauna Kea. Habitat destruction has impacted many species but for birds like the U’au (Hawaiian petrel) their habitat is in very good shape but cats and other predators have driven them to the verge of extinction. An invasive species is any non-native animal or plant that has a negative impact on the economy, native species, or the environment including domesticated species such as pigs, goats, cattle, rats, horses, and cats. All of these these animals are problems that were created by arguably the most invasive species, humans and as a result we need to do something about it that is humane and effective.

      2. Nainoa March 19, 2018 7:59 pm Reply

        Then you support the killing of wildlife. Cats should not be kept in TNR colonies in public spaces, or anywhere that there is sensitive wildlife. Furthermore why not contain the cats? That would protect cats from threats like dogs and cars and protect wildlife. All you need is a fenced in area and a nifty rotating fence topper that prevents cats from escaping. Please don’t call yourself an animal advocate when all you are advocating for is the abandonment and maintenance of cats on the landscape.

        1. Irene Eklund November 28, 2018 3:14 pm Reply

          We all came from wild beginnings, so should we be euthanized too. I believe that no one should be able to have an animal dog or cat that is not spayed or neutered until the animal population is under control. So many homeless, mistreated animals in Hawaii.

    2. MKPatterson March 19, 2018 8:20 am Reply

      It is a freaking island, and this is just so sad that they don’t get it. NOTHING should come into that island that is NOT fixed, dog, cat, gerbals, nothing. It is a simple solution and ANY BREEDERS on the island or pet stores should not sell ANYTHING that is not spayed or neutered. That includes the damn military bases! I was military and I saw so many get orders and just leave their animals. I blame the Military also for not getting a handle on this in their housing rules. Ugg, any ISLAND needs to have this kind of law if it does not want the animals breeding out of control. It is such a simple solution. IRRESPONSIBLE PEOPLE have caused this PROBLEM, but they want to KILL instead of PREVENT. OK, I best stop.

  2. gordon oswald March 18, 2018 7:25 am Reply

    The State and County should stop putting little band aids on the wound and use stitches to close the wound all together, before we lose our birds! I’ve found 2, wild cat mutilated, dead Shamas in my yard over the past 3 months! Shamas are perhaps the most beautiful song birds on earth!! Put a bounty of $20 for every dead cat brought to the County and let the locals make some money by helping Kauai in a most significant way!! NOW!

    1. Jewls November 14, 2019 10:41 am Reply

      While cats killing birds is a problem that needs to be solved Shamas are not a Native species and were in fact introduced here as well.

  3. kauaiboy March 18, 2018 8:41 am Reply

    Seriously? No mention made of guinea grass? This invasive grass, which was introduced by selfish cattle ranchers and embraced by the GMO community to become even more drought resistant, is causing millions of dollars in maintenance cost, both to taxpayers and individual homeowners. Why are we acting like it doesn’t exist?

  4. harry oyama March 18, 2018 8:45 am Reply

    Toxoplasma is found in cat feces and urine and in this study, shown to cause high levels of cytokines to depression and violent suicide attempts in humans. https://blogs.scientificamerican.com/science-sushi/toxoplasmas-dark-side-the-link-between-parasite-and-suicide/

    In USA Today, a study shows that cats in America kill over 3.7 billion birds, 20.7 billion mammals each year. https://www.usatoday.com/story/news/nation/2013/01/29/cats-wild-birds-mammals-study/1873871/

    The governor is correct in placing feral cats on that list, catch, neuter and release will not solve the problem of native birds getting extinct and only makes the problem worst

  5. Uncleaina March 18, 2018 9:54 am Reply

    Finally!! Good job to come down on this TNR nonsense. Mr. Scott, you’ve got some creative math going on. The cats aren’t “community cats”…I’d challenge you to show me where our “communities” end and our wild spaces begin- you act like we’re a large metropolis- but a cat that lives in Kilauea “community” can walk 5 minutes and be in the middle of an endangered bird sanctuary…eating chicks. And toxoplasmosis spreads through water..so the “community”argument is invalid. So as I have said for over a decade, these “community cat” people are killing off our endemic and our endangered species and they need to stop! I want the state to step in and shut down the MASH they have coming up as it’s these same people catching and then releasing feral cats back into the wild. It should be illegal to do so. With some luck maybe our native species can recover from the damage done by feral cats. They still face other problems, but glad to see this one is coming to an end. Feral cats ARE an invasive species !

    1. Hope A.Duchaine March 18, 2018 9:28 pm Reply

      According to planet Earth, humans are an invasive species

      1. Uncleaina March 19, 2018 11:01 am Reply

        Did you know someone ALWAYS posts simpleminded comment?

    2. MKPatterson March 19, 2018 8:30 am Reply

      Toxo Comes from birds. New studies are showing that.

      1. Uncleaina March 19, 2018 11:00 am Reply

        That’s simply NOT TRUE. Toxoplasmosis has been studied in depth and it is found in cat feces. Pau.

      2. ruthann jones March 20, 2018 4:52 pm Reply

        cats carry Toxoplasmosis…hence physicians warn pregnant women to stay away from litter boxes, etc. Can do serious damage or death to fetus. Those who are severely allergic to cats also have problems as the dander exists even outdoors in areas with cats and it takes a long time to dissipate.

      3. Nainoa March 20, 2018 9:16 pm Reply

        Birds become infected by toxo by cats but cannot pass it on to other organisms. Toxo can only reproduce inside of felines, and domestic cats are the only felines in Hawai’i.

  6. Susan Flores March 18, 2018 12:43 pm Reply

    It was a human that started the cat problem, no cat wakes up and decided they no longer want a home , struggle to survive, live in all elements, run from abusive people , no that decisions was decided by a selfish cold hearted person that decided to dump their cat , not spay their cat or just don’t want the responsibility anymore. Human are the invasive species they destroy everything they touch

    1. M Hare March 19, 2018 1:23 am Reply

      I agree

      1. Uncleaina March 19, 2018 11:05 am Reply

        Yes so as humans we need to clean up this mess by euthanizing the feral cats. We already euthanize several thousand cats each year – we need to stop TNR so we can get a handle on the problem and unfortunately euthanizing the cats is the only way that’s effective.

  7. Susan Flores March 18, 2018 12:46 pm Reply

    Human are the invasive species, they dump their cats who only try to survive they only way they can , no cat wants a life where death is around every corner , a human made the decision for them

  8. JP March 18, 2018 2:02 pm Reply

    I dont understand how neutering a cat can be more effective at population control than euthanizing the cat. A dead cat is a neutered cat too…
    The #’s dont make sense.

  9. Alita March 18, 2018 4:06 pm Reply

    This is a such a load of hypocrisy.

    No one kills more other species than humans do. No other species is as invasive as humans are. Hawaii, are you going to list humans as an invasive species?

    Put your money where your mouth is, people. Its a waste of time whining about cats when they can’t hold a candle to the devastation caused by humans.

    If you really want to help, focus
    resources on HUMAN devastation.

    Otherwise, you simply just are not serious.

    Grow up, Hawaii.

    1. Uncleaina March 19, 2018 11:11 am Reply

      So if humans are an invasive species in Hawaii – feel free to move away. Nobody is stopping anyone who feels this way from leaving. Leave! This article is about feral cats – not about the environmental impact of humans.

    2. Nainoa March 19, 2018 8:23 pm Reply

      Humans are with out a doubt a major problem but part of that problem is the species we move around including cats. Also not all species are heavily impacted by humans but are instead devastated by things like cats especially in islands like Hawai’i. Part of allocating funds to address the impacts by people is by necessity going to have to go to invasive species if we ever want to start to make a difference.

  10. Aa March 18, 2018 4:55 pm Reply

    What about humans?

    1. Tam March 19, 2018 7:09 am Reply

      Well said, Alita.

  11. Kelley March 18, 2018 7:19 pm Reply

    Cats do not just pop up in the wild out of the blue all by themselves, the problem starts with people. Maybe people should start taking responsibility for their pets instead of dropping them off and abandoning them parking lots, woods, random neighborhoods, etcetera. I can guarantee they dont want to be homeless, hungry, or left to fend for themselves. Theres nothing wrong with trap and RELEASE, but to put down over 23,000 cats because people dont like ferel cats walking around outside bc they’re “invasive” is kind of ridiculous!? Im not even sure how anyone claims they’re that invasive when ferel cats will not even walk up to people.

    1. Nainoa March 19, 2018 8:19 pm Reply

      Its absolutley peoples fault which is why we need to do something to address the issue. Species here in Hawai’i are down from millions to just a few hundred or thousand because of cats and other invasive mammals. Invasive species are any species that has negative impacts on the environment or the economy. U’au (Hawaiian petrel) used to number in the millions in Hawai’i but today less than 5,000 remain. They were very important because their poop was fertilizer for the native forests without this the forests are also starting to decline. Cats may run away from people but they are definitely having negative effects on the environment. Trap and release is bad wildlife because after being released the cats can still kill wildlife. It’s also bad for cats disease is more prevalent when cats are kept in large numbers, cats are more likely to be hit bar cars or killed by dogs, and they do not receive proper veterinary care unless they can be caught again (very unlikely).

  12. Michael Freitas March 18, 2018 8:04 pm Reply

    We should put Politicians at the top of the list. They’re the biggest invasive species all over the U. S.

    1. diane March 19, 2018 4:32 am Reply

      *snort* hah! You are absolutely correct!

  13. ruthann jones March 19, 2018 5:33 am Reply

    i SUPPORT eradication of feral cats on Kauai….maybe impose a $1,000 fine for the little old ladies who feed them? That should do the trick if enforced!

    1. MKPatterson March 30, 2018 12:07 pm Reply

      Fines should be any persons on the island that do not fix their pets. PERIOD. YES, it is very true birds can also cause damage and carry toxo,. Does anyone realize that? That cats do not constantly shed but only for a few days? Then that is it? I have many studies now starting to get the TRUTH out about Toxo. Please get the WHOLE story and not just the hype. However, this is an island and nothing absolutely nothing should be sold in pet shops or privately, given away, nor imported. The breeders need to be highly taxed and cats need to be tracked if not fixed. Here is just one line I have about the bird connection on Toxo and the amount of money it is costing Ag and other areas. I do not advocate killing of any species, but people have made the feral cat problem and it will not stop until very tough laws exist. It is nonsense that people are allowed to have pets and not care for them correctly. http://www.birdgard.com/health-hazards-of-bird-droppings/

  14. Dan Melone March 19, 2018 5:39 am Reply

    It’s the same tired old routine. Cat advocates bring up one false claim as an argument for TNR. Someone explains why it is false. They have no rebuttal so they simply jump to the next false claim on their list.

    “Humans are worse”

    Explain how cats are an extension of the human hand of destruction and how all threats must be addressed.

    “The vacuum effect”

    Explain how this is a human contrivance due to all the food dumped by feeders, and that if it were true it would apply whether the TNR cat got hit by a car or was removed and euthanized.

    “Colony cats keep other cats away”

    Explain how cats wouldn’t form colonies in the first place if they were territorial, and how feeders talk about new cats joining their colonies all the time. Site Levy’s study that states cats are not territorial.

    “My ferals don’t kill any birds”

    Explain how they can’t possibly know that since they only see the cats briefly each day and cats don’t return the majority of their kills.

    “Well, my cats don’t kill MANY birds”

    See above explanation.

    “Well, my cats only kill sparrows and starlings”

    See above explanation again

    “The Smithsonian Study has been debunked”

    Explain how there is not one single scientist with a relevant degree working in a relevant field who has disputed Loss, Will, Marra. Only cat advocates dispute it. Peter Wolf is a spoon designer with no scientific degree. Barbara King is an anthropologist and “animal ethicist”. Steve Dale is a columnist and “animal behavior consultant”. Mark Bekoff is an animal behaviorist and does not work in a relevant field.

    “So then we should remove hawks, owls, and other predators that kill birds”

    Explain that those are native animals that belong in the ecosystem, unlike cows and sheep and cats, which are domestic and do not.

    “You won’t get toxoplasmosis unless you’re eating cat poop”

    Explain how toxoplasmosis is actually spread and that 60 million Americans are infected.

    “Well, toxoplasmosis is only an issue for pregnant women and aids patients”

    Explain the 4000 people blinded by toxoplasmosis and the mental disorders suspected of being linked to it and how all of us will have diminished imuno-competency as we age.

    “TNR cats are protected from rabies and are a buffer between humans and wild animals for rabies.”

    Explain how every rabies vaccine requires a booster that these cats never get and that there is no initial shot that is good for 3 years and that there is no science indicating that one shot for these cats is protective.

    “If you get rid of the cats we’ll be overrun with rodents”

    Explain how North America was not overrun with rodents for the millions of years prior to the arrival of cats. Explain how rodents are attracted to all the cat food dumped everywhere and how integrated pest control can control rodents.

    “If not TNR, then what?”

    Explain how pet cats must be controlled with licensing, containment, tagging, and neutering laws, and existing ferals controlled by removal, feeding bans, and public education.

    And their favorite: “It works!!!!!!!!!!!!!”

    Explain that there is no municipality anywhere in North America or the world that can claim that it has reduced its feral cat population through TNR and provide the data to prove it. Not one.

    1. Uncleaina March 19, 2018 11:06 am Reply

      Great post Dan – you are spot on. These people give the same excuses; meanwhile up in Kokee another bird gets eaten by a feral cat.

      1. MK Patterson March 31, 2018 5:24 pm Reply

        Please we look forward to meeting you in the Dakota’s at the annual meetings.

    2. Sarah Schmidt March 19, 2018 8:08 pm Reply

      Thank you! Very well said. Same old (weak) argument from the cat folks. Must be the toxo……

    3. MK Patterson March 31, 2018 5:22 pm Reply

      Oh Dan Melone, Thank you for calling the TRUE feral cat advocates to muster. you see, I do NOT believe in just feeding, I do NOT believe in letting feral cats suffer due to ignorance. Thank You sir, because you will hear of FACTS from many that I am gathering. It is because of ignorance and Myths that YOU BUY INTO, and the true ignorance of myths and not the ACTUAL: FACTS and education about Toxo and TNR that WILL be presented to the Western Governors Association. SO please be ready to put YOUR WORS/WRITTEN RHETORIC into ACTION. TIME has finally come! WE that agree TNR is the solution, you just have missed the message. So please keep on, since I hope I will see you at the Governors public meeting in June.

  15. Yvretta Carus March 19, 2018 11:35 am Reply

    What a strange way of calculating cat population reduction! The way to asses population is to count the cats, perform your manipulation (in this case, TNR) and then count the cats again. For a more meaningful population assessment, identify several cat colonies, randomly select some to be TNRed and treat the others with trap-remove, and count all cats before and after treatment. Counting only cats that have been processed does not give an accurate total. The cats can be counted by observing them at feeding stations.

  16. Kristen Butters March 19, 2018 1:47 pm Reply

    Good for the Gov, I wish every state would show the same care and concern for their human and wildlife residents.. I have know idea why the outdoor cat hoarder was given air time, if his cats are not really feral, he should take them home

  17. Geckoman March 19, 2018 4:42 pm Reply

    TNT – Trap N Terminate. Save the indigenous animals.

  18. Nainoa March 19, 2018 8:08 pm Reply

    Anyone else find flaws in the math in this article? How is 2,200 cats 18% when 23,000 cats is 10%? It seems like the trapping and euthanizing removed far more cats from the community.

    “KCCP has done TNR on 5,400 cats in the past decade and reduced the community cat population by 18 percent, or 2,200 cats, according to Scott.

    He pointed out that trapping and euthanizing 23,000 cats during that same time reduced the community cat population by 10 percent”.

    In fact if these numbers are correct TNR was only able to remove less than 10% of the cats that trapping and euthanizing was able to. Here is the math: 100%=23,000 cats removed from TNR = 2,200, divide 2,200 by 23,000 you get 10.45 meaning that TNR methods removed only 10.45% of what trapping and euthanizing removed.

  19. Cherry Martin March 20, 2018 8:26 am Reply

    Why not build a cat Sanctuary? It’s been great on Lanai as a big tourist attraction. Speaking of tourist, how do you think most of them will feel to see kitty cats being mass executed as is being suggested and what is that going to cost the taxpayers? Why not look for a solution for both parties? The majority of individuals that love cats is expansive worldwide and trust me, the world will be watching. It’s possible to think beyond the black and white and find a middle ground to work together.

  20. Sarah Schmidt March 21, 2018 9:43 am Reply

    invasive species:
    Species that are non-native to a particular ecosystem and whose introduction causes, or is likely to cause, economic or environmental harm. Invasive species are characterized by rapid growth rates, extensive dispersal capabilities, large and rapid reproductive output and broad environmental tolerance.

    Sounds like the definition of feral cats to me.

  21. Shirley Swaine March 22, 2018 10:29 pm Reply

    How did they invade? Have cats learned to be long distance swimmers, to row boats or charter ‘planes? They may be alien to Hawaii, but they are not invasive, they were introduced by the invasive species Homos sapiens and I suspect that now, given the habits of humans, were the cats not there, there would soon be a rodent problem in Hawaii, just as there was on the island of Macquerie (spelling) which decided to eradicate all the feral cats because they were preying on seabirds. What happened? The rat population exploded and killed more birds and the rabbit population exploded and denuded the island’s vegetation. It cost them multi-millions to rectify their mistake.

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