Rückgang von Bestand und Verbreitung des Auerhuhns Tetrao urogallus im Schwarzwald - Decline in Capercaillie Tetrao urogallus numbers and distribution area in the Black Forest.

Abstract

Decline in Capercaillie Tetrao urogallus numbers and distribution area in the Black Forest. Ornithol. Beob. 113: 235–248. Even though Capercaillie are still present in large parts of its original range, its numbers have decreased in many parts of the Western and Central European range and in several cases, local populations have gone extinct. The Capercail-lie population in the Black Forest, SouthWestern Germany, has undergone drastic declines in the past decades. In 1971 the number of male Capercaillie displaying at lekking sites throughout the Black Forest was counted for the first time, and since 1983 counts have been performed on a yearly basis. From 1993 onwards, all sightings and signs of Capercaillie presence have been documented and combined to create a distribution map, which is updated every five years. The lek-counts show fluctuations in the number of displaying males, but with a strong decline becoming evident over the entire study period: whereas roughly 450 males were counted between 1983 and 1994, the last count in 2016 revealed only 206 males. The decline was paralleled by a decline in range from 607 km 2 in 1993 to 457 km 2 in 2013. This 25 % decline is not evenly distributed in the Black Forest but is largest in the Southern and Eastern Black Forest («Süd-Schwarzwald» and «Baar-Schwarzwald») compared to the sub-populations in the Northern and Central parts of the study area. Possible causes include: habitat loss and deterioration, climate change, anthropogenic disturbance and increasing numbers of predators, most likely several of these operating in conjunction.

Full text

Der Ornithologische Beobachter / Band 113 / Heft 3 / September 2016 235
Rückgang von Bestand und Verbreitung des Auerhuhns
Tetrao urogallus im Schwarzwald
Joy Coppes, Judith Ehrlacher, Gerrit Müller, Klaus Roth, Karl-Eugen Schroth, Veronika Braunisch
und Rudi Suchant

&Tetrao urogallus
 



         
   
           





  

2   2   

 




         
       
  

 
       

        
        

  Tetrao urogallus   
    
     
  
      
    
      
   
    
     

236  

     
     

     
     
 
     
 


       

    




     

   
 

     
     
      
 
      
    
      
      
    
     
    

      
    
   
    
   
   

      
     

    

      
  
    
     
 


     
      




    
   
      


 
     
     
    
     
    
      
    
 
   

 

    
     
 
  

    
 

1. Untersuchungsgebiet, Material und
Methode
1.1. Untersuchungsgebiet und Auerhuhnschutz
Untersuchungsgebiet: 

 
    
     

     
     

  

     
    
     
 

   
   
   
      
      
   
     
     
     

     

    
    
  
    
    
  
  
    
     

  

Auerhuhnschutz im Schwarzwald: 
   
     
   
Abb. 1.

×





Capercaillie distribution in 2013,
shown in 3×3 km grid cells in the
four parts of the study area («Nord»
= north, «Mitte» = central, «Süd» =
south, and «Baar»). The shading in-
dicates the percentage of the grid cell
occupied by Capercaillie.

  




  
   
      

  
    
     
     
   
     
   
     
    

    


1.2. Datenerhebung
1.2.1. Populationstrend, Balzplatz-Monitoring
     
    
       
     
    
     

      

     
  
     
     
     
    
 



      

     
       
     
  
      
  


     
 
    
Abb. 2.




Their brown feathers
make the Capercaillie
females very well ca-
mouflaged.

  
      

 
    

       

   
     

     




     
   

  
 


 




 

1.2.2. Verbreitungsgebiete
    
    
  
   

    
   
     
     
     
   
     
     

     
  
   
 
     
   
    
     
 
   
     
   
 
Abb. 3.




The male Caper-
caillie is much more
conspicuous compared
to the female.

  
      

   
     
  
 
     
     


     
   
       
  
      

    


     
     
      


   



 
      
      
  


 

2. Ergebnisse
2.1. Bestandstrend nach den Ergebnissen des
Balzplatz-Monitorings
     

   
    
   
 
     

Abb. 4.      


Num-
ber of Capercaillie males counted at the leks in the Black Forest. The first count was carried out in the year
1971, since 1983 this was done every year. In 2013 a reliable count was not possible due to adverse weather
conditions. The countings are organized by the hunter’s associations: «Auerwildhegegemeinschaft» and the
Auerwildhegeringe «Freudenstadt» and «Calw».

  
    
      

    
       
      

     
         
      



      
     
      
      
     
    


       

     
Abb. 5.







The number
of males counted every
fifth year at the leks in
the four different parts
of the Black Forest.
As in 2013 a reliable
count was not possible
due to adverse weather
conditions, the data of
2012 are shown here.
Abb. 6.











An open
pine forest with blue-
berries in the northern
Black forest, the rich
ground vegetation pro-
vides cover and food
for the adult birds. Due
to the warmth there
are many insects as an
important resource for
the young birds.

  
 
        
 
      

2.2. Verbreitungsgebiete
       
     
     
 
     
        
 
     
   
     
     
     
3×     
  
     
 
  

      

Abb. 8. 





The area in-
habited by Capercaillie
per year, illustrated for
each part of the study
area (Nord» = north,
«Mitte» = central,
«Süd» = south, and
«Baar») and the total
area («Gesamt»).
Abb. 7.







Mean
number of males per
lekking site (± standard
deviation) in the four
parts of the study area.
Below each column the
number of lekking sites
is indicated.

  
   
      
       
     
      
2     2  


      2 
     
     
 
 2 
     


 



3. Diskussion
3.1. Datengrundlage
      
 
      
  
 




    
    
    


      
 
   

    
      
      
    


     
     

3.2. Bestandsrückgang


     

     
Abb. 9.







Change in per-
centage of the area in-
habited by Capercaillie
since 1988– 1993 per
year illustrated for the
four parts of the study
area («Nord» = north,
«Mitte» = central,
«Süd» = south, and
«Baar») and the entire
Black Forest («Ge-
samt»).

  
      

     
       
 
       
   
      

   
     
   
 

     
  
      
     
      
   
    
 
       
  
    

      

     
 
   
      
  
     

        
     
     

    
 
 
      
  

  

3.3. Potenzielle Rückgangsursachen
   
    
      
    

    
      
      
       
      

     
 
      
    
    
     
 
   


 
      
    
 
 
     
    
     
    
     
Abb. 10.       
 
 For the survival of
the population the raising of Capercaillie chicks is
essential.

  

 
    

    

  
  
     

      

    
    Vu l-
pes vulpes  Accipiter gentilis 
      


       
   
     
    
      
    

    
    
 
      
    


      
 
    
 
 



3.4. Fazit
    

    


    
     
   
 

      
   


Dank.    
     
  
   
     
     
    
     
     
     



  

 
     


Zusammenfassung, Résumé
Tetrao urogallus
  
Abb. 11.
   
      
     
 Both integrated within normal forestry
as well as with specific measures, one can improve
capercaillie habitats.

  



 
 
     
     

 
      
 


 
  

       
     
     

  2      
 2     
   

     

    
  


Régression de l’effectif et de l’aire de répartition
du Grand Tétras Tetrao urogallus en Forêt Noire
  Tetrao urogallus  
         
      
       

      
    
  
 
         
    
      
     
 

       


   
        

     
       
  2     2   

      
   

        
      
     
 


Literatur
       
   &  
(1   
   
    
  

  &


    &   
   
       
     

    &   
    
 
   




  (2 Tetrao urogallus 


&
 Tetrao urogallus   
   


  &    
   
 


  &    
     
     
     

&
(2 



&   
    


  
&  
      
 
   Tetrao urogallus
 
  &    
Tetrao urogallus


  &     
     
(Tetrao urogallus    
   
      
      

&
       
Vulpes vulpes


    

  &     
        

&

    

   
 

        & 
     
  

Tetrao urogallus





(2
    
    
   
   
 

  
&

    
    

        &


&
  
Tetrao urogallus
  


&   

 
 

    
    


       
 &  


& 
    
    
    
   

      
    
      

  
     

&Tetrao urogallus
   
    

&  
Tetrao uro-
gallus

      

&
      



  &     
 


      
Tetrao urogallus

      &  
(2  Tetrao urogallus 


      

&
 Tetrao uro-
gallus   
   


  
      


  
Tetrao
urogallus
   Tetrao urogallus 

  
  

  & 



    &    
    
Accipiter gentilis  
   

  &    
 
     
    
   


       
&       
     

&
(2Tet -
rao urogallus

&
(Tetrao urogallus 
    


&   
 
Tetrao urogallus

&  
Tetrao urogallus

& 

 
&  
      

& 
     
   

Manuskript eingegangen 4. März 2016
Bereinigte Fassung angenommen 31. Mai 2016
  
 Tetrao urogallus 
Tetrao tetrix
       
 


&
   Tetrao urogallus 



&  



        
    
       

  

  

&
     
        
 &  

 
  

&
      


&



Tetrao urogallus 


     

& 
Tetrao urogallus

     
  


       





Tetrao urogallus

      
       