Tritophic phenological match-mismatch in space and time

Increasing temperatures associated with climate change may generate phenological mismatches that disrupt previously synchronous trophic interactions. Most work on mismatch has focused on temporal trends, whereas spatial variation in the degree of trophic synchrony has largely been neglected, even though the degree to which mismatch varies in space has implications for meso-scale population dynamics and evolution. Here we quantify latitudinal trends in phenological mismatch, using phenological data on an oak–caterpillar–bird system from across the UK. Increasing latitude delays phenology of all species, but more so for oak, resulting in a shorter interval between leaf emergence and peak caterpillar biomass at northern locations. Asynchrony found between peak caterpillar biomass and peak nestling demand of blue tits, great tits and pied flycatchers increases in earlier (warm) springs. There is no evidence of spatial variation in the timing of peak nestling demand relative to peak caterpillar biomass for any species. Phenological mismatch alone is thus unlikely to explain spatial variation in population trends. Given projections of continued spring warming, we predict that temperate forest birds will become increasingly mismatched with peak caterpillar timing. Latitudinal invariance in the direction of mismatch may act as a double-edged sword that presents no opportunities for spatial buffering from the effects of mismatch on population size, but generates spatially consistent directional selection on timing, which could facilitate rapid evolutionary change

Artificial coastal lagoons at solar salt-working sites: A network of habitats for specialised, protected and alien biodiversity

There are concerns that novel structures might displace protected species, facilitate the spread of nonindigenous species, or modify native habitats. It is also predicted that ocean warming and the associated effects of climate change will significantly increase biodiversity loss within coastal regions. Resilience is to a large extent influenced by the magnitude of dispersal and level of connectivity within and between populations. Therefore it is important to investigate the distribution and ecological significance of novel and artificial habitats, the presence of protected and alien species and potential vectors of propagule dispersal. The legacy of solar salt-making in tropical and warm temperate regions is regionally extensive areas of artificial hypersaline ponds, canals and ditches. Yet the broad-scale contribution of salt-working to a network of benthic biodiversity has not been fully established. Artisanal, abandoned and historic salt-working sites were investigated along the Atlantic coast of Europe between southern England (50 N) and Andalucía, Spain (36 N). Natural lagoons are scarce along this macrotidal coast and are vulnerable to environmental change; however it is suspected that avian propagule dispersal is important in maintaining population connectivity. During bird migration periods, benthic cores were collected for infauna from 70 waterbodies across 21 salt-working sites in 5 coastal regions. Bird ringing data were used to investigate potential avian connectivity between locations. Lagoonal specialist species, some of international conservation importance, were recorded across all regions in the storage reservoirs and evaporation ponds of continental salinas, yet few non-indigenous species were observed. Potential avian propagule transport and connectivity within and between extant salt-working sites is high and these artificial habitats are likely to contribute significantly to a network of coastal lagoon biodiversity in Europ

Migratory connectivity and effects of winter temperatures on migratory behaviour of the European robin Erithacus rubecula: A continent-wide analysis

Many partially migratory species show phenotypically divergent populations in terms of migratory behaviour, with climate hypothesized to be a major driver of such variability through its differential effects on sedentary and migratory individuals. Based on long-term (1947-2011) bird ringing data, we analysed phenotypic differentiation of migratory behaviour among populations of the European robin Erithacus rubecula across Europe. We showed that clusters of populations sharing breeding and wintering ranges varied from partial (British Isles and Western Europe, NW cluster) to completely migratory (Scandinavia and north-eastern Europe, NE cluster). Distance migrated by birds of the NE (but not of the NW) cluster decreased through time because of a north-eastwards shift in the wintering grounds. Moreover, when winter temperatures in the breeding areas were cold, individuals from the NE cluster also migrated longer distances, while those of the NW cluster moved over shorter distances. Climatic conditions may therefore affect migratory behaviour of robins, although large geographical variation in response to climate seems to exist.We thank Dr. Dario Massimino (BTO) for providing population indices for UK. JJC was supported by the Spanish National Research Council (grant EST001196)

Data from: Migratory connectivity and effects of winter temperatures on migratory behaviour of the European robin Erithacus rubecula: a continent-wide analysis

1. Many partially migratory species show phenotypically divergent populations in terms of migratory behaviour, with climate hypothesized to be a major driver of such variability through its differential effects on sedentary and migratory individuals. 2. Based on long-term (1947–2011) bird ringing data, we analysed phenotypic differentiation of migratory behaviour among populations of the European robin Erithacus rubecula across Europe. 3. We showed that clusters of populations sharing breeding and wintering ranges varied from partial (British Isles and Western Europe, NW cluster) to completely migratory (Scandinavia and north-eastern Europe, NE cluster). 4. Distance migrated by birds of the NE (but not of the NW) cluster decreased through time because of a north-eastwards shift in the wintering grounds. Moreover, when winter temperatures in the breeding areas were cold, individuals from the NE cluster also migrated longer distances, while those of the NW cluster moved over shorter distances. 5. Climatic conditions may therefore affect migratory behaviour of robins, although large geographical variation in response to climate seems to exist

Data from Robin migration and climate change

Variable name description: ID = ID for individual robins (progressive numbers); Lat2 = Latitude of the site where Robin was recovered during wintering; Lon2 = Longitude of the site where Robin was recovered during wintering; Lat1 = Latitude of the site where Robin was recovered during breeding; Lon1 = Longitude of the site where Robin was recovered during breeding; Year = Year when a robin was recovered in winter (from November of year i to February of year i + 1); Country = Country where a robin was observed during the breeding period; gridID = ID of the 2.5 ° lat x 2.5° lon cell where the robin was observed during the breeding period; Cluster = Cluster to which the robin belong, as assessed by migratory connectivity analysis; DistMig = migration distance calculated as the great-circle (orthodromic) distance between breeding and wintering position (km); CminT = temperature anomaly for the cell where the robin was observed breeding during the winter when it was recovered in winter (°C); CmaxTS = temperature anomaly for the cell where the robin was observed breeding during the summer when it was recovered in winter (°C); CminAT = temperature anomaly for the cell where the robin was observed breeding during the autumn when it was recovered in winter (°C); CminT1 = temperature anomaly for the cell where the robin was observed breeding during the winter preceding the one when it was recovered in winter; pop.index = population index in the country where a robin was observed breeding in the year when it was recovered in winter (index in the reference year = 0); Adult = whether a robin was adult or young when recovered in winter

Spatiotemporal data on pedunculate oak leafing and peak frass dates for the UK

Data to accompany paper on “Tritrophic mismatch in space and time”. Observations are on the phenology of oak first leaf date and the peak caterpillar frass date across the UK for the period 1998 to 2016.Burgess, Malcolm; Smith, Ken; Leech, David; Pearce-Higgins, J; Branston, Claire; Briggs, Kevin; Clark, John; Evans, Karl; du Feu, Chris; Lewthwaite, Kate; Nager, Ruedi; Sheldon, Ben; Smith, Jeremy; Whytock, Robin; Willis, Stephen; Phillimore, Albert. (2017). Spatiotemporal data on pedunculate oak leafing and peak frass dates for the UK, 1998-2016 [dataset]. University of Edinburgh. http://dx.doi.org/10.7488/ds/2215

Variable responses to large-scale climate change in European Parus populations.

Spring temperatures in temperate regions have increased over the past 20 years and many organisms have responded to this increase by advancing the timing of their growth and reproduction. However, not all populations show an advancement of phenology. Understanding why some populations advance and others do not will give us insight into the possible constraints and selection pressures on the advancement of phenology. By combining two decades of data on 24 populations of tits (Parus sp.) from six European countries, we show that the phenological response to large-scale changes in spring temperature varies across a species' range, even between populations situated close to each other. We show that this variation cannot be fully explained by variation in the temperature change during the pre- and post-laying periods, as recently suggested. Instead, we find evidence for a link between rising temperatures and the frequency of second broods, which results in complex shifts in the laying dates of first clutches. Our results emphasize the need to consider links between different life-history parameters in order to predict the ecological consequences of large-scale climate changes

Tritrophic phenological match-mismatch in space and time

Increasing temperatures associated with climate change may generate phenological mismatches that disrupt previously synchronous trophic interactions. Most work on mismatch has focused on temporal trends, whereas spatial variation in the degree of trophic synchrony has largely been neglected, even though the degree to which mismatch varies in space has implications for meso-scale population dynamics and evolution. Here we quantify latitudinal trends in phenological mismatch, using phenological data on an oak–caterpillar–bird system from across the UK. Increasing latitude delays phenology of all species, but more so for oak, resulting in a shorter interval between leaf emergence and peak caterpillar biomass at northern locations. Asynchrony found between peak caterpillar biomass and peak nestling demand of blue tits, great tits and pied flycatchers increases in earlier (warm) springs. There is no evidence of spatial variation in the timing of peak nestling demand relative to peak caterpillar biomass for any species. Phenological mismatch alone is thus unlikely to explain spatial variation in population trends. Given projections of continued spring warming, we predict that temperate forest birds will become increasingly mismatched with peak caterpillar timing. Latitudinal invariance in the direction of mismatch may act as a double-edged sword that presents no opportunities for spatial buffering from the effects of mismatch on population size, but generates spatially consistent directional selection on timing, which could facilitate rapid evolutionary change