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Pollinator decline, driven primarily by habitat degradation, has the potential to reduce the quantity and quality of pollinator-dependent crops produced across the world.  Vitellaria paradoxa, a socio-economically important tree which grows across the sub-Saharan drylands of Africa, produces seeds from which shea butter is extracted. However, the habitats in which this tree grows are threatened with degradation, potentially impacting its ability to attract sufficient pollinators and to produce seeds. The flowers of V. paradoxa are insect-pollinated, and we investigated flower visitors in six sites in southern Burkina Faso and northern Ghana and tested whether plants were capable of fruit set in the absence of pollinators. We found that the majority of flower visitors (88%) were bees, most frequently small social stingless bees (Hypotrigona gribodoi), but native honey bees (Apis mellifera adansonii) were also common visitors to flowers early in the morning. The number of fruit produced per inflorescence was significantly lower when insects were excluded during flowering by bagging, but any fruits and seeds that were produced in bagged treatments were of similar weight to un-bagged ones. We conclude that conservation of habitat to protect social bees is important to maintain pollination services to V. paradoxa and other fruit-bearing trees and cultivated crops on which local livelihoods depend.

Populations of long‐distance migrant birds are declining but it is unknown what role land cover change in non‐breeding areas may be playing in this process. Using compositional analysis, we assessed habitat selection by one such migrant, the Wood Warbler Phylloscopus sibilatrix, at a wintering site in the forest–savannah transition zone in Eastern Region, Ghana. There was a preference for forest, a habitat that is in marked decline at this site. Annual habitat mapping revealed that the area of forest declined by 26% between 2011/12 and 2013/14, mainly through clearance for conversion to arable land. Numbers of birds changed throughout the season, but despite the reduction in the preferred forest habitat, there was no change in the total number of birds recorded at the site over the study period. The number of birds recorded at a point was positively related to the proportion of cleared land, plantation and, to a lesser extent, dense forest within 100 m. Investigation of the fine‐scale habitat preferences of radiotagged Wood Warblers suggested that there was an optimum number of trees, around 66–143 per hectare, at which estimated probability of occupancy was 0.5, falling to a probability of 0.2 at 25 trees per hectare. We suggest that Wood Warblers may be buffered against the loss of forest habitat by their ability to utilize degraded habitats, such as well‐wooded farmland, that still retain a substantial number of trees. However, the continued loss of trees, from both forest and farmland is ultimately likely to have a negative impact on wintering Wood Warblers in the long‐term.

Land use change in sub‐Saharan Africa continues apace, but its role in driving the declines of Afro‐Palaearctic migrant birds is unknown. This is due partly to a lack of knowledge of migrants’ requirements on the wintering grounds, and of spatially explicit assessments of land cover change. We compared tree cover data derived from satellite remote sensing (available for the period 2000–2014) with distributional data from surveys in four West African countries for the Wood Warbler Phylloscopus sibilatrix, one such declining migrant, to determine the extent of, and change in, optimal tree cover. Wood Warblers were most likely to occur where tree cover per hectare was between 40 and 61% (optimal tree cover). Extrapolation to the whole of the wintering range indicated there was a 46.7% net increase in extent between 2000 and 2014. This was due to an alarming 27 683 km2 of previously closed forest being degraded from > 61% cover to between 40 and 61%, an area greater than that of the optimal tree cover that was lost. Increases in optimal tree cover were greatest in countries with greatest forest cover, such as Sierra Leone, Liberia, Côte d'Ivoire and Democratic Republic of Congo. The results suggest that loss of optimal tree cover in the wintering range might not be a key driver of population decline for Wood Warblers, but the degradation will probably impact species that rely upon dense tree cover.

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