RSPB LETTER

[wings]

I have Just recieved this e-mail from the RSPB ref the letter that i sent them earlier this week, WHAT DO YOU ALL THINK, i'am not convinced that the sparrow hawk has had a negative growth, i would think that the hawk population would increase yearly while there is plenty of food and only when it finds food hard to come by will it start to stabalise.

 

(The question of this species of bird of prey is an emotive one given that they are often active in our gardens. Sparrowhawk populations have been recovering from persecution that took place in the early part of the 20th century. Over the last few years, the population has stabilised and there was even a negative growth (less than 1%) last year.

 

The figures themselves are quite enlightening when it is considered that there are 26 species that are confirmed as prey for the hawks. The population of sparrowhawks is estimated at 64,000 whereas the prey species is 45,299,800. If each hawk took one prey item per day then the potential kill rate would be 23,360,000. This figure would be well within the extinction rate for many of the prey species. However, this is not the whole story and the hawks do not take prey at a consistent rate. Although they may take a bird on three consecutive days, it is likely that they will not feed on subsequent days. Flying weight is a key consideration to all birds and if they were to feed more often then they simply would not be able to take off. This is not the end of the maths because we also have to consider the potential reproductive capacity of the prey species. For the 26 species on the list, this comes out at 472,388,400 individual birds. Given those figures, it is impossible for the sparrowhawks to make any impression on the overall figures. It has to be remembered that the population figure relates to an annual total and this means there is a tremendous wastage of birds to other causes. In terms of your question, there is actually no reason to control sparrowhawks, as there is no evidence that they are affecting population levels of other birds.

 

Regards

 

Ian Peters - Wildlife Advisor

The Lodge,

SANDY.

Bedfordshire.

SG19 2DL            

Tel: 01767 693690        

[chickadee]

I have Just recieved this e-mail from the RSPB ref the letter that i sent them earlier this week, WHAT DO YOU ALL THINK, i'am not convinced that the sparrow hawk has had a negative growth, i would think that the hawk population would increase yearly while there is plenty of food and only when it finds food hard to come by will it start to stabalise.

 

(The question of this species of bird of prey is an emotive one given that they are often active in our gardens. Sparrowhawk populations have been recovering from persecution that took place in the early part of the 20th century. Over the last few years, the population has stabilised and there was even a negative growth (less than 1%) last year.

 

The figures themselves are quite enlightening when it is considered that there are 26 species that are confirmed as prey for the hawks. The population of sparrowhawks is estimated at 64,000 whereas the prey species is 45,299,800. If each hawk took one prey item per day then the potential kill rate would be 23,360,000. This figure would be well within the extinction rate for many of the prey species. However, this is not the whole story and the hawks do not take prey at a consistent rate. Although they may take a bird on three consecutive days, it is likely that they will not feed on subsequent days. Flying weight is a key consideration to all birds and if they were to feed more often then they simply would not be able to take off. This is not the end of the maths because we also have to consider the potential reproductive capacity of the prey species. For the 26 species on the list, this comes out at 472,388,400 individual birds. Given those figures, it is impossible for the sparrowhawks to make any impression on the overall figures. It has to be remembered that the population figure relates to an annual total and this means there is a tremendous wastage of birds to other causes. In terms of your question, there is actually no reason to control sparrowhawks, as there is no evidence that they are affecting population levels of other birds.

 

Regards

 

Ian Peters - Wildlife Advisor

The Lodge,

SANDY.

Bedfordshire.

SG19 2DL            

Tel: 01767 693690        

 

Yeah well they would say that wouldn't they. >

[homer]

all they are trying to do is baffle our brains with "numbers"

 

the bottom line is this .....they stated      "there is no evidence that they are affecting population levels of other birds."

 

 

 

 

well i'll tell you what mister , talk to the members on this site (that span the uk) and i think you will find that the population of birds in their sheds is very much affected by the sparrow hawk !

 

 

 

 

[chickadee]

all they are trying to do is baffle our brains with "numbers"

 

the bottom line is this .....they stated      "there is no evidence that they are affecting population levels of other birds."

 

 

 

 

well i'll tell you what mister , talk to the members on this site (that span the uk) and i think you will find that the population of birds in their sheds is very much affected by the sparrow hawk !

 

 

 

 

Maybe they'll start to get the picture if we keep on pestering them. ;D

[Guest bristolkev]

what a load of B******s > >

[wings]

Im verys uprised that the original thread has not shown more interest, as this noy just the garden birds we are talking about, have people forgot about are pigeons