Beyond the effects of temperature increase on local population trends and on species distribution shifts, how populations of a given species are affected by climate change along a species range is still unclear. We tested whether and how species responses to climate change are related to the populations locations within the species thermal range. We compared the average 20 year growth rates of 62 terrestrial breeding birds in three European countries along the latitudinal gradient of the species ranges. After controlling for factors already reported to affect bird population trends (habitat specialization, migration distance and body mass), we found that populations breeding close to the species thermal maximum have lower growth rates than those in other parts of the thermal range, while those breeding close to the species thermal minimum have higher growth rates. These results were maintained even after having controlled for the effect of latitude per se. Therefore, the results cannot solely be explained by latitudinal clines linked to the geographical structure in local spring warming. Indeed, we found that populations are not just responding to changes in temperature at the hottest and coolest parts of the species range, but that they show a linear graded response across their European thermal range. We thus provide insights into how populations respond to climate changes. We suggest that projections of future species distributions, and also management options and conservation assessments, cannot be based on the assumption of a uniform response to climate change across a species range or at range edges only.

Aims:  To analyse the occurrence and host species distribution of campylobacteria species in shorebirds, geese and cattle on grazed coastal meadows in Sweden. Methods and Results:  Species identification was performed through a polyphasic approach, incorporating Amplified Fragment Length Polymorphism (AFLP) profiling, 16S RNA gene sequence analysis together with extensive phenotypic characterization. From 247 sampled birds and 71 cattle, we retrieved 113 urease positive thermophilic Campylobacter (UPTC) and 16 Campylobacter jejuni ssp. jejuni isolates. Furthermore, 18 isolates of Helicobacter canadensis, and five isolates that potentially represent a new genus of micro‐aerophilic, spiral and Gram‐negative bacteria were isolated. The distribution of bacterial species on hosts was uneven: all H. canadensis isolates were retrieved from geese, while all but one of the Campylobacter lari UPTC isolates were found in shorebirds. AFLP type distribution of Camp. lari UPTC isolates among individual, resampled and breeding‐paired Redshank birds generally indicated a constant shift in strain populations over time and absence of geographical clustering. Conclusions:  The large number of isolated campylobacteria, including species that are zoonotic enteropathogens, indicates that these wild birds potentially may serve as reservoirs of human infections. However, despite a common environment, the different host species largely carried their own campylobacteria populations, indicating that cross‐species transmission is rare. Significance and Impact of the Study:  Our study is one of few that provide data on the occurrence of campylobacteria in wild animals, adding information on the ecology and epidemiology of micro‐organisms that are of public health concern.

A polyphasic identification approach was used to investigate the taxonomic position of Campylobacter-like isolates recovered from barnacle geese (Branta leucopsis) and Canada geese (Branta candensis). Seven strains were selected from a collection of 21 isolates and analyzed by extensive phenotypic testing; four strains were characterized by 16S rRNA gene sequence analysis. The results clearly identified the bird isolates as Helicobacter canadensis, recently described as an emerging human pathogen. This is the first report of an animal reservoir for this organism and of its presence in Europe and confirms the zoonotic potential of H. canadensis.Helicobacter canadensis, a recently described species closely resembling the enterohepatic zoonotic agent Helicobacter pullorum (5), is one of many new enteropathogens isolated from humans (1, 16). The clinical importance of this bacterium is not fully established, but it has been isolated from fecal samples of patients with enteritis (5) and from a blood culture of a patient with bacteremia (19). It has been described as an emerging pathogen (5). No animal host has hitherto been identified for H. canadensis but its closest taxonomic relative, H. pullorum, is found in poultry and retail chicken products (3,17). Here, the presence of H. canadensis in wild birds is reported for the first time and the zoonotic potential of this bacterium is discussed.A study on the transmission, ecology, and epidemiology of Campylobacter spp. (in particular Campylobacter jejuni and Campylobacter lari) in cattle and wild birds on pastured meadows in Sweden has been conducted (J. Waldenström et al., unpublished data). Fieldwork was conducted at a shore meadow on southern Gotland, southeast Sweden, where a flock of approximately 1,000 barnacle geese (Branta leucopsis) settled for 4 weeks during spring migration in 2001. To obtain samples, the flock was disturbed and sterile cotton swabs were used to collect fecal material from fresh goose droppings. Care was taken not to touch the surrounding grass, and each of the 116 samples was placed in charcoal transport medium (Transwab; BioDisc, Solna, Sweden) and stored at 4 to 8°C in a refrigerator until cultivation. Samples were then plated onto Campylobacter selective blood-free medium (45.5 g of Campylobacter selective agar base LAB M/LAB 112/liter, 2 ampoules of cefoperazone-amphotericin supplement LAB M/X 112; IDG (UK) Limited, Bury, England) and incubated at 42°C in a microaerobic atmosphere (85% N 2, 10% CO 2 , 5% O 2 ) for 72 h, at which time the media were examined for bacterial growth. Presumptive identification as Campylobacter spp. was done by limited phenotypic characterization (cell morphology and oxidase, catalase, and hippurate hydrolysis).For detailed genetic identification, the 23 Campylobacterlike isolates obtained were characterized by amplified fragment length polymorphism (AFLP)-based profiling. Chromosomal DNA was purified from bacterial cultures with the Puregene DNA isolation kit (Gentra Systems, Minneapolis, Minn.) according to...

The taxonomic status of populations of rockhopper penguins (Eudyptes chrysocome) is still enigmatic. Northern populations differ from southern ones in breeding phenology, song characteristics and head ornaments used as mating signals. We conducted a molecular analysis using mitochondrial DNA sequencing to test if there is a gene flow barrier between northern (subtropical) populations and southern (subantarctic) populations in relation to the Subtropical Convergence, a major ecological boundary for marine organisms. Sequences of the control region and the ND2 gene were analysed in rockhopper penguins and in the macaroni penguin (Eudyptes chrysolophus), a closely related species. Genetic distances and phylogenetic analyses showed a clear split into three clades, two rockhopper clades and the macaroni penguin. Moreover, Theta(ST) and gene flow estimates also suggested genetic structuring within the northern rockhoppers. Our results add further support to the notion that the two rockhopper penguin taxa, often considered as two subspecies, can be recognized as two species E. chrysocome and E. moseleyi. The divergence in mating signals found between these two taxa seems to have occurred recently and relatively rapidly. Thus, the behavioural changes may have been enough to isolate these taxa without the need for morphological differentiation. The findings have important conservational implications, since E. moseleyi is far less abundant than E. chrysocome, but more populations may warrant an uplisting to endangered status if full species status should be recognized for more subpopulations.

Kubelka et al. (Reports, 9 November 2018, p. 680) claim that climate change has disrupted patterns of nest predation in shorebirds. They report that predation rates have increased since the 1950s, especially in the Arctic. We describe methodological problems with their analyses and argue that there is no solid statistical support for their claims.