Saturday, 7 December 2013

Flagship species and bird conservation

Our research at Loddington has shown how management of a wild game species, in our case pheasants, is associated with increases in a wide range of other bird species, including Biodiversity Action Plan species such as song thrush and spotted flycatcher.  Other GWCT monitoring has revealed increases in skylarks and corn buntings in response to management carried out for grey partridges.  Management for one species can benefit others, and iconic flagship species can serve as indicators of conservation benefits to other species.

However, some long term monitoring I have been contributing to in Portugal suggests that we should not always assume that this relationship holds.  The Alentejo region of southern Portugal is an interesting mixture of relatively intensive irrigated farming (including arable crops and olives), and traditional extensive steppe incorporating fallows within low input arable rotations which form a Natura 2000 area.  These low input systems are a haven for globally threatened species such as great bustard and lesser kestrel, but also a range of other steppe species such as short-toed and calandra larks. Agri-environment schemes are in place to maintain populations of the iconic flagship species which bring income to the area as an attraction for bird watchers.  In a paper in Conservation Letters*, we present the findings of our monitoring, comparing bird numbers in the 1995-1997 period with the present day.
Great bustards in front of a lesser kestrel colony site in the Alentejo study area               © C Stoate
Both great bustards and lesser kestrels responded well to the agri-environment schemes, relative to the control areas without such management.  The surprise was that other steppe birds did not. In the paper, we discuss various potential causes for this discrepancy, but the honest answer is that we don't know. One possible influence is that agricultural policy that resulted in replacement of low input cereal crops with more specialised livestock systems countered the positive effects of the agri-environment scheme management for some species.  At least in this southern European environment, it seems that we cannot always assume that the status of iconic flagship species necessarily reflects that of the other species that share the same habitat. The ecological requirements of all target species may need to be considered in designing agri-environment scheme management options.

Santana, J., Reino, R., Stoate, C., Borralho, R., Rio Carvalho, C., Schindler, S., Moreira, F., Bugalho, M., Flores Ribeiro, P., Lima Santos, J., Vaz, A., Morgado, R., Porto, M., Beja, P. Mixed effects of long-term conservation investment in Natura 2000 farmland. Conservation Lettersdoi: 10.1111/conl.12077

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