Dreaded cormorents

"The easiest way to control the cormorant populations, without shooting a single bird, would simply be to prick a few eggs. "

In a word - rubbish!

I am amazed that a professional scientist can come up with this solution!! It is nonsense for some very simple reasons which are well documented and well researched.

The basic problem is that sea birds are long lived, a cormorent can probaly live 20 - 30 years. In that time it has the potential to lay (approximately) 15 cutches of eggs. I havn't the faintest how many eggs in a typical cormorent clutch, say 2.

This means that, over their life time, each pair or cormrents will produce 30 eggs.

If the poulation is to remain stable, then two of these have to be succesfully reared. So their is already ~87% mortality built into the system.

This is a vital aspect to the biology of birds - egg production is excesive to produce a 'reservior' of production which allows the population to increase when food suplies are plentiful. Evan a small increase in survival can have a large impact on the overall population oevr a period spanning several years.

It also means that, within quite wide ranges, the population can remain stable in the face of a substantial increases in hatching failure (i.e. egg smashing). Fewer eggs hatch out, so fewer mouths to feed so more chicks survive so poulation recovers.

This is all basic stuff - a lot of it is based upon experience gained during an earlier sea bird population explosion, when gulls invaded a lot of coastal cities. Sunderland was particularly badly affected and had a substantial egg smashing campaign.

To have any significant impact on a bird population you have to *continuously* smash a *lot* of eggs for a long time.

The abundance of predatory species is determined by the abundance of prey. There *must* be enough fish in the geographical range of the birds to support the population. If there was not, the birds wouldn't be there.

And before anyone says it, I know that cormerants can clean out a pond and then move onto the next one. What's more, like pike, most sea birds *are* canibalistic and if food suplies go will prey on each others chicks like no tomorrow.

If you want to solve the cormorent problem, then a 20 year ban on stocking of rainbow trout into reservoirs throughout the UK might do the trick. This creates environments with unrealistic fish populations that attract fish eating birds, which then do serous damage to neighboring, natural environments.

Can't see it happerning, and the number of birds you would have to cul just wouldn't be feasible so finding ways to live with the probelm may be the answer.

"Pricking a few eggs" isn't "rubbish" at all.It's worked quite well to control Canada geese in the USA.Cormorants lay three to four eggs so pricking( or shaking) the eggs does make a dent in the following years poulation but only if done on a large enough scale.Of course we shoot the geese as well but shaking the eggs pretty much drove them off our golf course.

Canada goose population is going up as well! I'm afraid you almost certainly just moved them onto somewhere else.

The cormorent population explosion is only one of a series of similar increases in bird poulations. Kittiwake and herring gulls in the late 60s / early 70s, pigeons in 50s / early 60s are probably the best examples.

A lot of time and effort has been put into egg spiking methods and studies. If it makes you feel happier please spike as many eggs as you can get access to and shoot as many birds as you like. Unless you get to a very substantial proportion of the eggs and keep it up for a long time (i.e longer than a birds life) it will have little effect on the overall population.

This is because hatching success is *not* the factor that limits population growth. There is actually a huge *overproduction* of chicks. The factor that almost invariably limits the population of colonial breeding birds is access to the nest sites themselves.

The birds actually compete with each other to get access to the breeding colony, so at almost every stage in the life cycle there is a huge 'reserve' that can fill any vacancies created in the population.

This is why colonial breeding birds are so succesful.

I see the Countryside Alliance are on the case of Cormorants maybe they will make headway.

"A Twenty year ban on the stocking of rainbow trout into reservoirs!"

What about a total ban on the stocking of toy carp into the many thousands of commercial waters in this country instead?

The best way of ridding this country of cormorants is the have a 20 year ban on inshore commercial sea fishing!

That would take the cormorants back to where they really belong.

I'm right, aren't I?

i think Rons right!!!!
(he always is!)

apart from the bit about "toy carp"
(thats BOLLOCKS!)

Then if I am talking "bollocks", why are toy carp stocked in such huge numbers.

Whats wrong with indigenous fish?

roach, tench, bream, RUDD (about time we stocked more of this lovely species), perch etc.

nothing RON, i love all indigenous species.....
"toy carp" are stocked in huge numbers to give people with too much money and not enough skill the chance to get a tug every now and then!.....
surely the same as stocking trout in a lake, when really they should be in a river (i thought)
As for cormerants, according to clubs new liscense, shooting them seems to do some good, although the liscence only allows us to shoot 2 a month i think!!!!... how come if these birds are such a problem, the take up of shooting liscences is so low?.

it's about time the experts and scientists did a study on how cormarants are affecting our inland fish stocks, and did something to protect them instead of cormarants.

Nick Austin 2, my club (or one of them) shoots the things legally.It is not difficult to get licences it just takes a little effort.As a result this club has the best silver fish stocks for some considerable distance.The waters are not pools or rivers but big 30 plus acre gravel pits.Cormorants know where to avoid and on this clubs waters they stil turn up but are off at the merest sign of an angler. A water a mile down the road is a different story, they just ignore anglers and carry on destroying the stock.

PIKE - Barries comments are spot on. "God's Handle" is my term for lifting pike by the chin. It's all gelatinous stuff and bone under there so long as you keep away from gill plates, so little harm ceom to the pike as far as I'm concerned.

It's a damned sight better method of handling them than the old gaffs. gags, and stringers. Ugghhh!

--

On cormorants - yes, improving the fish stock around our coast might help. Stopping ship disasters like the Sea Empress would also help - for anyone thinking that mess was all cleaned up the sea bed was (and probably still is) caked in oil.

Personally, I'd like to give shooting them a go. A dead bird can't eat. Some of them are not sea birds any more, of COARSE.

My club has a license to cull 4 birds a month.
Given that earlier this season you would regularly see upwards of two dozen Cormorants at any one time on just one of our lakes the 4 bird limit is something of a joke, in all reality.
That said, I do not believe that the answer lies completely in culling this menace.
A complete solution is needed and needed sooner rather than later.

Strangely enough, I never seem to hear, or talk to any of the local fly anglers who complain about Cormorants.
Maybe this is because most of the locals also shoot as well as fish?

Yes Peter, remeber the comments of that bailiff on the Avon near Salisbury.

Yes I think Ron is right!! We don't have baby carp fisheries up here.

Up here there used to be ~200 Cormorents roosting under the Tay rail bridge.

They are non there now, but numbers at previusly small inland roosts near have all gone up. All three roosts are near lochs heavily stocked with rainbows and who can blame the cormorenst for uping sticks and moving there. There are 20+ boats out on each loch throughout the season, and I suppose everyone wants a decent bag to take home, so that adds up to a lot of fish. A natural fishery just couldn't suupport that level of fishing pressure.

Ron,
I certainly do remember that conversation.
It seems to be the same "conversation" down on the Nadder and the Wylyie too

Although, as I noted above, I think that culling is only a part solution and that a complete solution has to be found.

I'm certainly not questioning Barries advice on handling pike but I'm sure I have seen somewhere that holding the pike vertically is bad for them. Something to do with the gravitational pressure on the internal organs. Is this true?

yes, i thought that only being able to cull two per month was a joke too, but apparently it acts as a great deterent to the other cormerants too!...
Certainly info from my club bailiff suggests they are really pleased with the results......
next comes the mink hounds.... i'm not half as sure about that though!

POSTED ON BEHALF OF BARRIE RICKARDS:

Stuart Wilson's comments are critical but nonetheless welcome. Pricking eggs is far from satisfactory and it is, as he says, a slow business, but had this been started when the cormorant problem was first recognised as very serious, namely 10-12 years ago, then we'd by now have made considerable progress. Pricking eggs on a regular basis is fairly straightforward, much more so than shooting.

The idea of banning the stocking of rainbow trout into reservoirs would not help our coarse fisheries much would it? Might even make matters worse. The culling of cormorants which took place in the sea-bordering fenland areas in the 1950s and 1960s certainly kept the cormorants under control, but I'm not sure of all the methods that were used.

Ron Clay is right, of course. He's saying what some of us said originally. The only problem then becomes getting us out of the EC, which caused the problem in the first place.

To Baz: the work has been done, and some of it most critical of cormorants has been swept under the carpet. The letter from Tony Wainwright on handling pike was interesting. There was an argument made along those lines some years, ago, by a man in the Bristol area whose name I now forget. I didn't agree with it then and I don't now. It's all down to speedy and careful handling really. The main problem with both gag and gaff was that they were downright inefficient and did not allow rapid handling.

Barrie Rickards

Professor Barrie Rickards
Dept Earth Sciences, University of Cambridge

Interesting comments from Barrie.

As regards rainbow trout.

This species is different from others in that it is a game fish and whether you agree with it or not, it is stocked to eventually be killed and eaten. Rainbow trout are the fishy equivalents of pheasants.

Pheasants were introduced into this country to be reared and shot for sport and food. They are not designed to live very long.

Rainbow trout if never caught and killed do not live very long either. 5 years at the outside and often not as long as that if they are cocks. Rainbow trout provide a great deal of sport and omega 3 to anglers who fish for them.

I am very much against the common practice of total catch and release trout waters. In time the trout in these waters get virtually impossible to catch on the fly rod.

I do like the idea of having a ticket where you can kill say two or three fish and then release say another four or five. Have a limit bag like this and surely that should satisfy any angler.

I don't like the idea of catching and releasing large numbers of trout in a day's fishing. I have done it in the past, but I have not been proud of it.

If you want to spread your fly fishing over a whole day, why not try to be more selective regarding the fish you catch. For example sit quietly by the water and only cast to a rising fish, or fish you can see.

Trout can, at times, be ridiculously easy to catch, even on the fly.

Any angler worth his salt does not want easy fishing.