domingo, marzo 28, 2010

English summary 2010

English summary
Red kite population evolution in Navarra (northern Spain)
Navarra is a region of around 10.000 km2 located in the northern part of Spain, along the Spanish/French border, and to the south of the Pyrenees. The navarran population of Red Kites was first thoroughly monitored twice in the 90’s during the 92/93 and 93/94 wintering seasons and then continuously counted in the 2000’s for the last 10 winters.
The results of the last wintering season are presented in this report. The average of the population estimate for the navarran population for the 12 census done is 2.265. The total count for the 2009/2010 wintering period was only 1.599 individuals what represents 33 % less than the average. It also represents a decrease of 18 % versus the precedent year and 40 % since the maximum value obtained in 05/06.
The navarran wintering population of Red kite is distributed among 20-21 roosting areas, each one having a variable number of roosting places.
This winter season 2 red kites were found death in a wind-farm and the trees supporting two roosting places were cut during the season, forcing the birds to move somewhere else. This population seems to be very dependent on the public dumping areas and this is the potential reason for the significant changes observed in the distribution of the kites inside the region in the last few winters when several dumping areas were closed and dumping activities concentrated in a few places.


census count

population estimate


92/93

2181

2290


93/94

2147

2254

-1,56%

00/01

2142

2249

-0,23%

01/02

2026

2229

-0,91%

02/03

1673

2008

-9,92%

03/04

2522

2522

25,62%

04/05

2137

2244

-11,03%

05/06

2615

2667

18,87%

06/07

2175

2240

-16,01%

07/08

1894

1951

-12,92%

08/09

1866

1959

0,43%

09/10

1539

1613

-18,38%

Average

2151

2265