S
Stuart Wilson
Guest
"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.
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.