7 ms·

Mapping the “catscape” formed by a population of pet cats with outdoor access

61 points by lode 4y ago

mensetmanusman 4y ago
“Catscape” inversely maps to “birdscape”
- falcolas 4y ago
  Not necessarily, if you're implying that cats predate birds efficiently. Cats are fairly lax, in a manner of speaking, in catching birds. Mice, voles, gophers, and rabbits are easier to catch and more plentiful. We'll see them catch maybe one bird a month. In contrast, the number of birds in our area is innumerable. We'll get hundreds at our feeders every day, and see dozens of songbirds (Robins, Atarlings, Red Winged Blackbirds, Magpies, Woodpeckers, Pigeons, etc.) while driving into town. And that's without getting in the raptors (some of whom are a threat to cats). I imagine humanity's reduction of bird's habitats has a bigger impact than the carnivores we bring with us.
  - reaperducer 4y ago
    the number of birds in our area is innumerable You are very lucky. The last place I lived, the birds almost all disappeared over the course of about five years. When i first moved there, I couldn't sleep past 5:30am because of the raucous dawn chorus. There were always birds around, and i had several feeders for them all. By the time I moved away, the chorus was one bird. Maybe. And the feeders never got used. From what I read on the internet, this is becoming more and more common.
    - marcinzm 4y ago
      Is that due to cats or the drop in insect populations which many birds feed on?
      - vwcx 4y ago
        Insects, but the cats don't help.
    - d4mi3n 4y ago
      Domestic cats are VERY successful hunters in general, with the highest success rates of all animals in that kingdom. That said, I don’t know what success looks like over different kinds of prey. Over the last year or so we’ve also had a pretty bad outbreak of avian flu which has done a lot to depress bird populations—though my understanding is it has been mainly farmed chickens and turkeys that have been hard hit.
      - shagie 4y ago
        That title is held by the black footed cat - https://www.livescience.com/63992-deadliest-cat.html https://www.livescience.com/63992-deadliest-cat.html > In one night, a black-footed cat kills between 10 and 14 rodents or small birds, averaging a kill about every 50 minutes, according to Hunter. With a 60 percent success rate, black-footed cats are about three times as successful as lions, which average a successful kill about 20 to 25 percent of the time, Hunter said. Compare with the domestic house cat - https://doi.org/10.1111/acv.12563 https://doi.org/10.1111/acv.12563 > Owners reported that their pets killed an average of 3.5 prey items/month, leading to an estimated ecological impact per cat of 14.2-38.9 prey ha^−1 yr^−1. This is similar or higher than the per-animal ecological impact of wild carnivores but the effect is amplified by the high density of cats in neighborhoods. As a result, pet cats around the world have an ecological impact greater than native predators but concentrated within ~100 m of their homes. Related... https://www.nature.com/articles/ncomms2380 https://www.nature.com/articles/ncomms2380 > We estimate that cats in the contiguous United States annually kill between 1.3 and 4.0 billion birds (median=2.4 billion) (Fig. 1a), with ∼69% of this mortality caused by un-owned cats. The predation estimate for un-owned cats was higher primarily due to predation rates by this group averaging three times greater than rates for owned cats.
        jhugo 4y ago
        > Owners reported that their pets killed an average of 3.5 prey items/month I think owners would not be aware of a lot of a cat's hunting activity if it has access to the outdoors.
        4y ago
    - RajT88 4y ago
      I live by a river. There is such a thriving bird population these days thanks to improving regulations on dumping in the river, I am pretty sure cats are prey. There is a massive red tailed hawk population. And a moderate Bald Eagle population. Hell, we have started getting Pelicans the last few years, and I simply would not put it past them to swallow a moderate sized mammal. The Canada Geese and turkeys would win in a fight any day. It is anecdotal, but it seems to me as waterways become less polluted, you are starting to see these sorts of animals return to even dense urban areas like Chicago.
      - Spooky23 4y ago
        Nobody is talking about Canada geese. Cats eviscerate songbirds and other small birds. My son and I are actually gathering data of bird populations in our immediate area. We live in an urban area where half the block consists of 2-3 family apartments. Our yard is a bird highway due to where our home is placed and the trees. The tenants tend to migrate in cohorts. We noticed anecdotally that the bird population grew a year after a few key neighbors, who kept outdoor cats and were cat people who fed strays, moved away. It’s a difficult issue as like many things, extreme behavior drives extreme outcomes. I’d like to understand the impact of house cats vs mentally ill people who attract feral cats. (Or similar folks who attract disruptive populations of birds like pigeons)
  - t-3 4y ago
    Based on your birdlist, it sounds like we live in the same region, and I agree. The birds are all very social and will quickly mob an aggressive cat if the lookouts don't warn everyone in time.
- colechristensen 4y ago
  If you have an outdoor cat, plant an oak tree, they support hundreds of species of all sorts of animal which support bird populations.
- xoa 4y ago
  Any discussion about this is going to be highly dependent on local conditions. But having said that: my house is in a rural area delightfully flooded with birds, with a variety of bird feeders I put out and insects I try to support, and a number of indoor/outdoor hunting cats, and there are plenty of tools to keep cat birding down to darn near zero. The basic thing to reason about is how cats hunt and birds feed. Cats need to sneak close, then ambush in a burst of speed. Birds though have extremely fast reaction time and of course can go straight up. They don't need much. Cats also have limited ability to jump, and will go after other easier creatures most of the time if they can. So first, basic obstructions nearby the house/barn are kept low. I have some former field I've mowed down into lawn (full of whatever random stuff is around), there are some trees and rocks around, and that's it. There is plenty of field/woods full of approximately 12.45 billion chipmunks, mice and voles by my rough estimate, but small birds don't tend to ground feed there they and in brush off the ground. Cats can't sneak up well anywhere in the vicinity of feeders. I have the feeders themselves suspended off the ground with ropes between trees/buildings and a second rope going to pulleys so I can lower them for refilling and cleaning. The feeder bottoms are at least 9-11' off the ground and 10' from the nearest structure or tree. This renders them effectively invulnerable not merely to cats but conveniently squirrels, raccoons, and black bears. With some platforms mixed in, even ground feeders can get some aerial action. But most do want to be on the ground, and there all it takes is a small low wire fence. And by low I mean low, like a foot or two high maybe. It looks fine in the lawn and is easy to move, it's trivial to step over or for cats to hop over. But by forcing them to jump it destroys any last potential ambush or sprint. In the time they go vertical no bird will miss them and they lose speed. Even though cats can get over without the slightest difficulty it's amazing how they instantly don't even bother, guess they reason out right away that if they have to leap into the air well before their target it's pointless to even try. They don't stalk birds at all at this point just wander by. The only remaining threat is bird strikes on windows. Cats figure out that noise pretty fast and will go to investigate if they're in the area (which they often aren't granted). No perfectly solution there except to aim to reduce bird strikes which is a good goal anyway. I use a mix of screens and stickers. Window screens as well as their core function of keeping out insects while letting in air are excellent shock absorbers and reflection disrupters for birds. The normal downside is they do interfere with views (and the enjoyment of bird watching to some extent), but high density enhanced visibility screens like UltraVue/BetterVue can help lesson that tradeoff. For windows where screens aren't doable or truly are undesirable (particularly in winter) I use WindowAlert stickers. They actually blend pretty well with windows, being fairly translucent in visible light, but reflect very strong in UV which most birds (particularly song birds) can see but we cannot. They're chemical so they have to be replaced every 4-6 months but are quite effective. I also use some regular visible stickers that simulate spider webs which birds instinctively avoid. A bit of thought and effort and you can have quite a lot of wildlife living together reasonably well, and that includes a good number of feline friends. Totally natural lawn field, seeding some wildflower meadows, decent varieties of flora with no poisons, carpenter bee houses and so on can all give insects a boost too.
- msrenee 4y ago
  We just moved here. I saw a Brown Thrasher on my wood pile. Bit of a weird place for one, but cool. Then I saw the neighbor's cat take a flying leap at it. Now I'm thinking it would be irresponsible of me to put out a feeder or attract birds with this cat running around. Which is kind of a big deal for me. I'm trying to work out how to explain to the neighbors that I love cats, but my yard is my yard and I have a right to not have their cat in it killing birds.
  - aaaaaaaaata 4y ago
    They'll probably be working out for a bit how to explain to you that the cat doesn't take specific commands well.
    - msrenee 4y ago
      Being as we're in town and there are laws against letting the cat roam free, it would more be a discussion of your cat is chasing birds on my property. Do something about it.
  - turtledove 4y ago
    In most jurisdictions outdoor cats are not allowed. If you can identify the owner of the cat, you can file a complaint. Here in Seattle, if several complaints are filed the person may eventually have to surrender their cat. Don't let your cats outside, folks. They kill wildlife, destroy gardens, and poop everywhere.
    - gelert 4y ago
      Speaking from the UK I have to say that is insane. Like all animals, humans included, cats belong outdoors and to deprive them of their natural rhythms is cruel. I agree that we need to think about how to nurture bird populations but keeping cats pent up indoors is wrong - and is reflected by how much worse they behave when that is done.
      - paulryanrogers 4y ago
donavanm 4y ago
If anyone else is interested I believe the study area is approx 59.65 N 10.79 E, just south of Ås 1430 Norway.
layer8 4y ago
Now I want Catscape Navigator.
- SemanticStrengh 4y ago
  It turns out this exist https://starmade-shadows.tumblr.com/ https://starmade-shadows.tumblr.com/ One could say Internet is cat-complete.
- amelius 4y ago
  Perhaps using a Garmin GPS watch as a collar will give you what you want?
markstos 4y ago
I wonder how these outdoor predation numbers compared to the number of animals killed to make their cat food and the number of animals killed for their owners to eat.
- AlexandrB 4y ago
  I think a more relevant question is how much natural habitat is destroyed by the factory farms that are used to make pet food. The number of farmed animals killed is kind of irrelevant when you're talking about the health of wild populations.
- Perenti 4y ago
  I don't think these numbers are comparable. To the best of my knowledge one cow can fill many cans of cat food, whilst a cat may eat many geckos in a day. Similarly I may eat an entire rabbit in a day, but it'll take a while for me to eat a sheep.
mostertoaster 4y ago
Yeah our cat killed too many birds so we put the bird bait (bird feeder) away. Still kills a good amount of mice though which is great.

61 points by lode 4y ago

mensetmanusman 4y ago

“Catscape” inversely maps to “birdscape”

falcolas 4y ago
Not necessarily, if you're implying that cats predate birds efficiently. Cats are fairly lax, in a manner of speaking, in catching birds. Mice, voles, gophers, and rabbits are easier to catch and more plentiful. We'll see them catch maybe one bird a month. In contrast, the number of birds in our area is innumerable. We'll get hundreds at our feeders every day, and see dozens of songbirds (Robins, Atarlings, Red Winged Blackbirds, Magpies, Woodpeckers, Pigeons, etc.) while driving into town. And that's without getting in the raptors (some of whom are a threat to cats). I imagine humanity's reduction of bird's habitats has a bigger impact than the carnivores we bring with us.
- reaperducer 4y ago
  the number of birds in our area is innumerable You are very lucky. The last place I lived, the birds almost all disappeared over the course of about five years. When i first moved there, I couldn't sleep past 5:30am because of the raucous dawn chorus. There were always birds around, and i had several feeders for them all. By the time I moved away, the chorus was one bird. Maybe. And the feeders never got used. From what I read on the internet, this is becoming more and more common.
  - marcinzm 4y ago
    Is that due to cats or the drop in insect populations which many birds feed on?
    - vwcx 4y ago
      Insects, but the cats don't help.
  - d4mi3n 4y ago
    Domestic cats are VERY successful hunters in general, with the highest success rates of all animals in that kingdom. That said, I don’t know what success looks like over different kinds of prey. Over the last year or so we’ve also had a pretty bad outbreak of avian flu which has done a lot to depress bird populations—though my understanding is it has been mainly farmed chickens and turkeys that have been hard hit.
    - shagie 4y ago
      That title is held by the black footed cat - https://www.livescience.com/63992-deadliest-cat.html https://www.livescience.com/63992-deadliest-cat.html > In one night, a black-footed cat kills between 10 and 14 rodents or small birds, averaging a kill about every 50 minutes, according to Hunter. With a 60 percent success rate, black-footed cats are about three times as successful as lions, which average a successful kill about 20 to 25 percent of the time, Hunter said. Compare with the domestic house cat - https://doi.org/10.1111/acv.12563 https://doi.org/10.1111/acv.12563 > Owners reported that their pets killed an average of 3.5 prey items/month, leading to an estimated ecological impact per cat of 14.2-38.9 prey ha^−1 yr^−1. This is similar or higher than the per-animal ecological impact of wild carnivores but the effect is amplified by the high density of cats in neighborhoods. As a result, pet cats around the world have an ecological impact greater than native predators but concentrated within ~100 m of their homes. Related... https://www.nature.com/articles/ncomms2380 https://www.nature.com/articles/ncomms2380 > We estimate that cats in the contiguous United States annually kill between 1.3 and 4.0 billion birds (median=2.4 billion) (Fig. 1a), with ∼69% of this mortality caused by un-owned cats. The predation estimate for un-owned cats was higher primarily due to predation rates by this group averaging three times greater than rates for owned cats.
      - jhugo 4y ago
        > Owners reported that their pets killed an average of 3.5 prey items/month I think owners would not be aware of a lot of a cat's hunting activity if it has access to the outdoors.
        4y ago
  - RajT88 4y ago
    I live by a river. There is such a thriving bird population these days thanks to improving regulations on dumping in the river, I am pretty sure cats are prey. There is a massive red tailed hawk population. And a moderate Bald Eagle population. Hell, we have started getting Pelicans the last few years, and I simply would not put it past them to swallow a moderate sized mammal. The Canada Geese and turkeys would win in a fight any day. It is anecdotal, but it seems to me as waterways become less polluted, you are starting to see these sorts of animals return to even dense urban areas like Chicago.
    - Spooky23 4y ago
      Nobody is talking about Canada geese. Cats eviscerate songbirds and other small birds. My son and I are actually gathering data of bird populations in our immediate area. We live in an urban area where half the block consists of 2-3 family apartments. Our yard is a bird highway due to where our home is placed and the trees. The tenants tend to migrate in cohorts. We noticed anecdotally that the bird population grew a year after a few key neighbors, who kept outdoor cats and were cat people who fed strays, moved away. It’s a difficult issue as like many things, extreme behavior drives extreme outcomes. I’d like to understand the impact of house cats vs mentally ill people who attract feral cats. (Or similar folks who attract disruptive populations of birds like pigeons)
- t-3 4y ago
  Based on your birdlist, it sounds like we live in the same region, and I agree. The birds are all very social and will quickly mob an aggressive cat if the lookouts don't warn everyone in time.
colechristensen 4y ago
If you have an outdoor cat, plant an oak tree, they support hundreds of species of all sorts of animal which support bird populations.
xoa 4y ago
Any discussion about this is going to be highly dependent on local conditions. But having said that: my house is in a rural area delightfully flooded with birds, with a variety of bird feeders I put out and insects I try to support, and a number of indoor/outdoor hunting cats, and there are plenty of tools to keep cat birding down to darn near zero. The basic thing to reason about is how cats hunt and birds feed. Cats need to sneak close, then ambush in a burst of speed. Birds though have extremely fast reaction time and of course can go straight up. They don't need much. Cats also have limited ability to jump, and will go after other easier creatures most of the time if they can. So first, basic obstructions nearby the house/barn are kept low. I have some former field I've mowed down into lawn (full of whatever random stuff is around), there are some trees and rocks around, and that's it. There is plenty of field/woods full of approximately 12.45 billion chipmunks, mice and voles by my rough estimate, but small birds don't tend to ground feed there they and in brush off the ground. Cats can't sneak up well anywhere in the vicinity of feeders. I have the feeders themselves suspended off the ground with ropes between trees/buildings and a second rope going to pulleys so I can lower them for refilling and cleaning. The feeder bottoms are at least 9-11' off the ground and 10' from the nearest structure or tree. This renders them effectively invulnerable not merely to cats but conveniently squirrels, raccoons, and black bears. With some platforms mixed in, even ground feeders can get some aerial action. But most do want to be on the ground, and there all it takes is a small low wire fence. And by low I mean low, like a foot or two high maybe. It looks fine in the lawn and is easy to move, it's trivial to step over or for cats to hop over. But by forcing them to jump it destroys any last potential ambush or sprint. In the time they go vertical no bird will miss them and they lose speed. Even though cats can get over without the slightest difficulty it's amazing how they instantly don't even bother, guess they reason out right away that if they have to leap into the air well before their target it's pointless to even try. They don't stalk birds at all at this point just wander by. The only remaining threat is bird strikes on windows. Cats figure out that noise pretty fast and will go to investigate if they're in the area (which they often aren't granted). No perfectly solution there except to aim to reduce bird strikes which is a good goal anyway. I use a mix of screens and stickers. Window screens as well as their core function of keeping out insects while letting in air are excellent shock absorbers and reflection disrupters for birds. The normal downside is they do interfere with views (and the enjoyment of bird watching to some extent), but high density enhanced visibility screens like UltraVue/BetterVue can help lesson that tradeoff. For windows where screens aren't doable or truly are undesirable (particularly in winter) I use WindowAlert stickers. They actually blend pretty well with windows, being fairly translucent in visible light, but reflect very strong in UV which most birds (particularly song birds) can see but we cannot. They're chemical so they have to be replaced every 4-6 months but are quite effective. I also use some regular visible stickers that simulate spider webs which birds instinctively avoid. A bit of thought and effort and you can have quite a lot of wildlife living together reasonably well, and that includes a good number of feline friends. Totally natural lawn field, seeding some wildflower meadows, decent varieties of flora with no poisons, carpenter bee houses and so on can all give insects a boost too.
msrenee 4y ago
We just moved here. I saw a Brown Thrasher on my wood pile. Bit of a weird place for one, but cool. Then I saw the neighbor's cat take a flying leap at it. Now I'm thinking it would be irresponsible of me to put out a feeder or attract birds with this cat running around. Which is kind of a big deal for me. I'm trying to work out how to explain to the neighbors that I love cats, but my yard is my yard and I have a right to not have their cat in it killing birds.
- aaaaaaaaata 4y ago
  They'll probably be working out for a bit how to explain to you that the cat doesn't take specific commands well.
  - msrenee 4y ago
    Being as we're in town and there are laws against letting the cat roam free, it would more be a discussion of your cat is chasing birds on my property. Do something about it.
- turtledove 4y ago
  In most jurisdictions outdoor cats are not allowed. If you can identify the owner of the cat, you can file a complaint. Here in Seattle, if several complaints are filed the person may eventually have to surrender their cat. Don't let your cats outside, folks. They kill wildlife, destroy gardens, and poop everywhere.
  - gelert 4y ago
    Speaking from the UK I have to say that is insane. Like all animals, humans included, cats belong outdoors and to deprive them of their natural rhythms is cruel. I agree that we need to think about how to nurture bird populations but keeping cats pent up indoors is wrong - and is reflected by how much worse they behave when that is done.
    - paulryanrogers 4y ago

donavanm 4y ago

If anyone else is interested I believe the study area is approx 59.65 N 10.79 E, just south of Ås 1430 Norway.

layer8 4y ago

Now I want Catscape Navigator.

SemanticStrengh 4y ago
It turns out this exist https://starmade-shadows.tumblr.com/ https://starmade-shadows.tumblr.com/ One could say Internet is cat-complete.
amelius 4y ago
Perhaps using a Garmin GPS watch as a collar will give you what you want?

markstos 4y ago

I wonder how these outdoor predation numbers compared to the number of animals killed to make their cat food and the number of animals killed for their owners to eat.

AlexandrB 4y ago
I think a more relevant question is how much natural habitat is destroyed by the factory farms that are used to make pet food. The number of farmed animals killed is kind of irrelevant when you're talking about the health of wild populations.
Perenti 4y ago
I don't think these numbers are comparable. To the best of my knowledge one cow can fill many cans of cat food, whilst a cat may eat many geckos in a day. Similarly I may eat an entire rabbit in a day, but it'll take a while for me to eat a sheep.

mostertoaster 4y ago

Yeah our cat killed too many birds so we put the bird bait (bird feeder) away. Still kills a good amount of mice though which is great.