The Wilson Journal of Ornithology 124( 1 ):51 -56, 2012 
PLASTICITY OF HABITAT SELECTION BY RED-BACKED SHRIKES 
{LANIUS COLLURIO) BREEDING IN DIFFERENT LANDSCAPES 
FEDERICO MORELLI 1 
ABSTRACT.—Environmental parameters in different breeding habitats of Red-backed Shrikes ( Lanius collurio) in 
central Italy were examined at altitudes ranging from 0 to 1.200 m. I he most suitable habitats lor breeding were. (I) 
cultivated areas with hedgerows, and (2) high altitude grasslands. Similar population densities were recorded in both 
habitats (0.27 pairs/10 ha in farmland vs. 0.30 pairs/10 ha in meadows) and as were the number of fledged young per 
breeding pair (3.38 in farmland vs. 3.75 in meadows). The structural characteristics of ‘open space' and 'edge density' 
differed in the two breeding habitats. Use of species of trees and bushes for nesting depended on habitat type, but nests were 
in die more abundant thorny shrubs (blackthorn | Primus spinosa) in farmland and juniper \Junipems communis | in 
meadows). Red-backed Shrikes in farmland appear to prefer to nest in the most heterogeneous territories, those with the 
presence of uncultivated areas and shrub patches. Plasticity of habitat selection by the species was evident. Reiei\ed _/ 
June 2011. Accepted 14 September 2011 
Characteristics of breeding territories of Red- 
backed Shrikes (Lanius collurio ) have previously 
been described in a number of studies (Cramp and 
Perrins 1993, Olsson 1995b. Lefranc and Worfolk 
1997, Harris and Franklin 2000. Guerriere and 
Castaldi 2006, Casale and Brambilla 2009). The 
greatest density of breeding pairs in Europe is in 
farmland ecosystems (Cramp and Perrins 1993, 
Parkas et al. 1997, Golawski and Golawska 2007) 
with these landscapes providing highly varied 
ecological conditions for many bird species and 
'beir prey (Golawski 2006). The Red-backed 
Shrike has been shown to prefer agricultural 
landscapes lhal are 'not intensively farmed' and 
are characterized by reduced functional heteroge¬ 
neity. This is especially true when there arc 
hedgerows and shrub patches that function as both 
key hahitat for many plants and animals, and 
wildlife corridors that enable dispersal and 
movement between habitats (Vermeulen 1994, 
Vcrmeulen and Opdam 1995). 
Habitats used for breeding have an essential 
n »le in the life-cycle of a bird, and many factors 
van influence the selection of breeding territories; 
two most important of which are minimization 
of predation (Cody 1985. Martin 1995. Roos 
-••021 and presence of adequate food (Martin 
'^7, Cramp and Perrins 1993, Golawski and 
Meissner 2008). 
The Red-backed Shrike is considered a I arm- 
land breeding species in the Marche Region ol 
Cen *ra| Italy (Pandolfi and Giacchini 1995, 
Forconi 2007. Morel I i et al. 2007). Hedgerows 
Jrc a familiar feature of most farmlands, and were 
OiSTcVA, University of Urbinp, Scientific Campus, 
6j 929 Urbino, Italy; e-mail: federico.morelli@uniurb.it 
traditionally planted as boundaries by both 
farmers and townspeople, albeit for different 
purposes. Currently, in areas which once had 
much greater coverage, they arc now only present 
as residual boundary lines of trees and shrubs, and 
are slightly >20 m in length and <5 m in width. 
Recent censuses indicate that Red-backed Shrikes 
may, however, use other habitat types for breed¬ 
ing in the Marche Region of central Italy (Forconi 
2007, Morelli et al. 2007). 
Detailed information about habitats and eco¬ 
logical requirements of a species is needed if it is 
to be successfully conserved. This is especially 
true for the Red-backcd Shrike which, except for 
a few areas of relative stability (PEC'BMS 2009), 
has experienced a marked population decline in 
western and northern Europe over the last three 
decades. The Italian population has been esti¬ 
mated at 50,000 lo 120,000 reproductive pairs 
(Birdlife International 2004), but with a negative 
trend (Meschini and Frugis 1993, Pandolfi and 
Giacchini 1995, Dinetti 1997). 
The causes of this decline are poorly under¬ 
stood. and it has been suggested that reduction 
in suitable habitats, habitat modifications, use of 
intensive agriculture systems, decline in food 
resources, and climatic changes are the main 
reasons (Tucker et al. 1994. Yosef 1994, Fuller 
et al. 1995). Rapid changes in agricultural 
ecosystems can result in the loss of a bird species 
in just a few years. Thus, it is important lo 
examine the ability of a species to colonize and 
breed in areas other than agricultural farmland. 
This is because the capacity to breed or forage in a 
greater number of habitat types can improve the 
survival potential of birds which settle in a 
territory that includes an optimal proportion of 
51 
