ChrisKten
It's true, I quite like Pigeons
Disclaimer: The following is advice from an amateur, not everything you read online is accurate 
Maybe some of what follows will be useful to others... it's a long read though, but if it helps one bird, it was worth the typing
Feeding the birds in your garden inevitably means seeing sick or injured birds... especially if Pigeons visit. You'll see some hobbled by netting - barely able to fly after escaping a Cat - lethargic, from being poisoned (the poison/drug is used to make them easier to catch, not meant to kill them... but makes them an easy toy for Cats to play with). Some will also be sick, with Pigeons, PMV, affects feral flocks each year... so does Canker (Trichomonosis), Botulism and Salmonellosis - the last three mentioned affects all birds, not just Pigeons.
Some of these diseases are treatable, some will run their course, some will kill the bird - either from starvation, dehydration, or from a predator noticing the bird is vulnerable (usually a pet cat). The larger birds are quite easy to catch, especially if you can see they're sick (birds hide their weakness until they no longer can (they don't want to stand out from the others), so if it looks ill, it's usually very ill). The smaller birds are very difficult to catch, unless you know what you're doing, or it's too late for the bird anyway.
So, what can you do? Most of the time, nothing - like I said, if you can see it's sick, it's probably very sick. If it's a small bird, I'd say that you're more likely to kill it while attempting to catch it (either from breaking it's tiny hollow bones, or from it becoming exhausted from trying to escape your failed attempts)... or injure yourself. If it's a large bird (Collared Dove +), you'll likely be able to catch it... but then what?
Some people will dispute this (especially if they've never actually taken a wild bird to a Vet), but in the UK, a Vet will treat a sick bird without charging you - this is due to the oath a Vet has to take concerning suffering (the words "cost" or "price" don't feature in the oath), and due to the majority of Vets actually caring about wildlife. So you could get the bird treated by a Vet... I've taken everything from Pigeons to Blackbirds to different Vets, all have been treated for free. Sometimes the treatment was just cleaning a wound, other times an anti-bacterial injection, sometimes euthanasia... like I said, I've never been charged.
If you've any Wildlife Rescue centres, they will help if they can (space and staff permitting). I've not tried the PDSA, or the RSPCA, as they need money rather than more work, but I'd guess they'd help too.
The last option (apart from; do nothing, or kill it), is to help it yourself - but if you do this, be prepared for disappointment, the bird may not survive the night, or may be too ill to recover, so die a few days later. Whatever the condition of the bird, don't be in a rush to water and feed it... it will probably be in shock from the ordeal of being captured (it assumes your going to eat it) a quiet dark place is the best initial treatment.
Trichomonosis, Botulism and Salmonella
(Symptoms can be similar... or not)
If you can catch it, get it to the Vets... unless you know what you're doing, in which case you need no amateur advice from me.
Hobbled Pigeon
Unlike sick birds, they can still react quickly and fly off, but they can't walk or run fast, so are possible to catch when feeding on the ground. If the string/nylon/netting is too tight, the best you can do is cut it in the middle to free the legs - leaving the rest on the feet will still give the bird a chance... although if it's very tight, the bird will probably lose a foot (now you know what happened to all those one-legged Pigeons in the street... in most cases, anti-roost netting).
Paramyxovirus (PMV)
PMV with Pigeons is a special case, as it's not fatal per se, but it is debilitating. Those worse affected often fly backwards, fall over, twist their heads up (Stargazing), spin round and round when stressed. By the time you see these symptoms, the virus has probably nearly run it's course, and quite a few Pigeons will survive. The best way to distinguish PMV from other causes, is the bird is otherwise well, they don't look ill, just a bit drunk. The trouble with PMV is it will spread through the flock (and other flocks), also some affected display no symptoms. Helping the rest of the birds might be your priority, and protecting those worse affected that can't defend themselves (they take too long to react, and have no chance against a cat). So bringing the bird inside will help the bird and prevent the virus spreading further. But there's two things to watch out for if you bring a Pigeon inside that has PMV: they often have fits and "zonk out", so can drown if the water you provide is too deep - so use a shallow dish. They also have poor coordination, so they can't peck at food accurately (they end up throwing food all over the place) - so you'll need to provide a deepish dish or cup with seeds so they can't miss.
However, the most important thing to bear in mind is this; Pigeons can take weeks to recover from PMV, many will be brain damaged (though still able to fly and fend for themselves) - some will never fully recover, and will never be able to be released... so you'll likely end up with a pet Pigeon. BTW, only consider a Rescue Centre if you are sure they can care for a bird with PMV, some will accept the bird, but kill it, as they don't have the facilities or staff for long-term care, and they don't want to risk the virus spreading to other birds they have.
BTW, I brought in a Pigeon with PMV about 11 months ago... it's still in a largish dog crate in my passage, and can only feed from a deep dish of seeds... it can't survive in the wild, but is otherwise well... and could live for another 10+ years (my wife is not particularly happy about this ). If you're lucky, you'll be able to release the bird in a few weeks, if you're unlucky, you'll have a pet
(I've not provided any info on treating other illnesses, because you'd need to be able to actually recognise what the illness is - a Vet can do that, I doubt you or I can)
*Feel free to add advice for stuff that I've not covered, or dispute anything that I have covered. Please base any advice on personal experience, not on anecdotes or urban myths. Or of course, based on training if you're a Rehabber or a Vet
Maybe some of what follows will be useful to others... it's a long read though, but if it helps one bird, it was worth the typing
Feeding the birds in your garden inevitably means seeing sick or injured birds... especially if Pigeons visit. You'll see some hobbled by netting - barely able to fly after escaping a Cat - lethargic, from being poisoned (the poison/drug is used to make them easier to catch, not meant to kill them... but makes them an easy toy for Cats to play with). Some will also be sick, with Pigeons, PMV, affects feral flocks each year... so does Canker (Trichomonosis), Botulism and Salmonellosis - the last three mentioned affects all birds, not just Pigeons.
Some of these diseases are treatable, some will run their course, some will kill the bird - either from starvation, dehydration, or from a predator noticing the bird is vulnerable (usually a pet cat). The larger birds are quite easy to catch, especially if you can see they're sick (birds hide their weakness until they no longer can (they don't want to stand out from the others), so if it looks ill, it's usually very ill). The smaller birds are very difficult to catch, unless you know what you're doing, or it's too late for the bird anyway.
So, what can you do? Most of the time, nothing - like I said, if you can see it's sick, it's probably very sick. If it's a small bird, I'd say that you're more likely to kill it while attempting to catch it (either from breaking it's tiny hollow bones, or from it becoming exhausted from trying to escape your failed attempts)... or injure yourself. If it's a large bird (Collared Dove +), you'll likely be able to catch it... but then what?
Some people will dispute this (especially if they've never actually taken a wild bird to a Vet), but in the UK, a Vet will treat a sick bird without charging you - this is due to the oath a Vet has to take concerning suffering (the words "cost" or "price" don't feature in the oath), and due to the majority of Vets actually caring about wildlife. So you could get the bird treated by a Vet... I've taken everything from Pigeons to Blackbirds to different Vets, all have been treated for free. Sometimes the treatment was just cleaning a wound, other times an anti-bacterial injection, sometimes euthanasia... like I said, I've never been charged.
If you've any Wildlife Rescue centres, they will help if they can (space and staff permitting). I've not tried the PDSA, or the RSPCA, as they need money rather than more work, but I'd guess they'd help too.
The last option (apart from; do nothing, or kill it), is to help it yourself - but if you do this, be prepared for disappointment, the bird may not survive the night, or may be too ill to recover, so die a few days later. Whatever the condition of the bird, don't be in a rush to water and feed it... it will probably be in shock from the ordeal of being captured (it assumes your going to eat it) a quiet dark place is the best initial treatment.
Trichomonosis, Botulism and Salmonella
(Symptoms can be similar... or not)
If you can catch it, get it to the Vets... unless you know what you're doing, in which case you need no amateur advice from me.
Hobbled Pigeon
Unlike sick birds, they can still react quickly and fly off, but they can't walk or run fast, so are possible to catch when feeding on the ground. If the string/nylon/netting is too tight, the best you can do is cut it in the middle to free the legs - leaving the rest on the feet will still give the bird a chance... although if it's very tight, the bird will probably lose a foot (now you know what happened to all those one-legged Pigeons in the street... in most cases, anti-roost netting).
Paramyxovirus (PMV)
PMV with Pigeons is a special case, as it's not fatal per se, but it is debilitating. Those worse affected often fly backwards, fall over, twist their heads up (Stargazing), spin round and round when stressed. By the time you see these symptoms, the virus has probably nearly run it's course, and quite a few Pigeons will survive. The best way to distinguish PMV from other causes, is the bird is otherwise well, they don't look ill, just a bit drunk. The trouble with PMV is it will spread through the flock (and other flocks), also some affected display no symptoms. Helping the rest of the birds might be your priority, and protecting those worse affected that can't defend themselves (they take too long to react, and have no chance against a cat). So bringing the bird inside will help the bird and prevent the virus spreading further. But there's two things to watch out for if you bring a Pigeon inside that has PMV: they often have fits and "zonk out", so can drown if the water you provide is too deep - so use a shallow dish. They also have poor coordination, so they can't peck at food accurately (they end up throwing food all over the place) - so you'll need to provide a deepish dish or cup with seeds so they can't miss.
However, the most important thing to bear in mind is this; Pigeons can take weeks to recover from PMV, many will be brain damaged (though still able to fly and fend for themselves) - some will never fully recover, and will never be able to be released... so you'll likely end up with a pet Pigeon. BTW, only consider a Rescue Centre if you are sure they can care for a bird with PMV, some will accept the bird, but kill it, as they don't have the facilities or staff for long-term care, and they don't want to risk the virus spreading to other birds they have.
BTW, I brought in a Pigeon with PMV about 11 months ago... it's still in a largish dog crate in my passage, and can only feed from a deep dish of seeds... it can't survive in the wild, but is otherwise well... and could live for another 10+ years (my wife is not particularly happy about this
). If you're lucky, you'll be able to release the bird in a few weeks, if you're unlucky, you'll have a pet (I've not provided any info on treating other illnesses, because you'd need to be able to actually recognise what the illness is - a Vet can do that, I doubt you or I can)
*Feel free to add advice for stuff that I've not covered, or dispute anything that I have covered. Please base any advice on personal experience, not on anecdotes or urban myths. Or of course, based on training if you're a Rehabber or a Vet
