Multiple signaling in a variable environment: expression of song and color traits as a function of ambient sound and light

Many animals communicate using more than one signal, and several hypotheses exist to explain the evolution of multiple signals. However, these hypotheses typically assume static selection pressures, and previous work has not addressed how spatial and temporal environmental variation can shape variation in signaling systems. In particular, environmental variability, such as ambient lighting or noise, may affect efficacy (e.g., detectability/perception by receivers) of signals. To examine how signal expression varies intraspecifically as a function of habitat characteristics, we evaluated relationships between spatial environmental variation and song and plumage color expression in a tropical songbird, the Red‐throated Ant‐tanager (Habia fuscicauda) in Panama. We recorded male ant‐tanager song, plucked feathers to measure coloration, and quantified the acoustic and light environments from each male's territory. In addition, we took several morphological measurements from each male to assess the potential information content of song and plumage color. We found that males with redder and more saturated crown plumage occurred on darker territories, and males that sang shorter and lower frequency songs occurred on noisier territories. We also found that more colorful males tended to sing longer and lower frequency songs. Finally, we found that song and color correlated similarly with male morphology (e.g., tarsus length, body mass). Altogether, these results indicate that spatial variation in the environment is related to male coloration and song, and that males might be optimizing color and song expression for their particular territorial environment.     

Associations between physical isolation and geographical variation within three species of Neotropical birds

We studied effects of physical isolation on geographical variation in mtDNA RFLP polymorphisms and a suite of morphological characters within three species of neotropical forest birds; the crimson-backed tanager Ramphocelus dimidiatus, the blue-gray tanager Thraupis episcopus, and the streaked saltator Saltator albicollis. Variation among populations within continuous habitat on the Isthmus of Panama was compared with that among island populations isolated for about 10000 years. Putative barriers to dispersal were influential, but apparent isolation effects varied by species, geographical scale, and whether molecular or morphological traits were being assessed. We found no geographical structuring among the contiguous, mainland sampling sites. Migration rates among the islands appeared sufficient to maintain homogeneity in mtDNA haplotype frequencies. In contrast, variation in external morphology among islands was significant within two of three species. For all species, we found significant variation in genetic and morphological traits between the island (collectively) and mainland populations. Interspecific variation in the effects of isolation was likely related to differential vagility. These data generally corroborate other studies reporting relatively great geographical structuring within tropical birds over short distances. Behaviourally based traits - low vagility and high ‘sensitivity’ to geographical barriers - may underlie extensive diversification within neotropical forest birds, but more extensive ecological and phylogeographic information are needed on a diverse sample of species.     

Effects of Single‐ and Mixed‐Species Group Composition on the Flight Initiation Distances of Plains and Grevy's Zebras

Zebras, as prey species, attend to the behavior of nearby conspecifics and heterospecifics when making decisions to flee from predators. Plains zebras (Equus quagga) and Grevy's zebras (E. grevyi) frequently form mixed‐species groups in zones where their ranges overlap in Kenya. Although anecdotal observations suggest that Plains zebras are more flighty around humans than Grevy's zebras are, this has not been empirically confirmed, and relatively little is known about how they may influence each other's flight behavior. We addressed these questions by examining the flight initiation distances (FIDs) of Plains and Grevy's zebras in single‐species and mixed‐species groups from an approaching human. One target individual per group was approached steadily on foot, with start distance, alert distance, and FID recorded from this target. Using start distance and alert distance separately as covariates, 22 Plains zebras in single‐species groups exhibited a significantly longer mean FID than 15 Grevy's zebras in single‐species groups. The FIDs of 7 Plains zebras and 5 Grevy's zebras tested in mixed‐species groups were virtually equivalent and intermediate to those of Plains and Grevy's zebras in single‐species groups, suggesting a bidirectional moderating influence of heterospecifics on risk assessment. This effect was most pronounced for Plains zebras in mixed‐species groups that exhibited an FID that was significantly shorter than that of Plains zebras in single‐species groups. Our findings underscore the importance of recognizing that related equids may be differently impacted by anthropogenic stress.     

Plasmodium paranucleophilum n. sp. from a South American Tanager*

SYNOPSIS. The avian malaria parasite described in this paper was isolated from a South American tanager of uncertain species, somewhat tentatively identified as belonging to the genus Tachyphonus. It is believed to have come from northern Brazil. Because the erythrocytic stages are, except for minor differences, similar to those of Plasmodium nucleophilum it is proposed to call it P. paranucleophilum. The chief difference separating the 2 species is the appearance of phanerozoites of the new species in lymphocytes of the circulating blood; these are characteristically vacuolated and give rise to moderate numbers of merozoites, probably in most cases 50 or less. Strains of P. nucleophilum isolated from other passerine birds also produce phanerozoites parasitizing lymphocytes, but such cells have never been observed in the blood stream. A subspecies, P. nucleophilum toucani, which we isolated from a Swainson's toucan Ramphastos swainsonii, also produces phanerozoites invading lymphocytes but it is less selective; endothelial cells of the brain are heavily attacked. It is also very lethal to canaries, whereas passerine strains of P. nucleophilum are usually quite benign. P. paranucleophilum, if the strain we have isolated is typical, lies between the 2 in pathogenicity, causing marked anemia but seldom death.     

Differences in seasonal survival suggest species‐specific reactions to climate change in two sympatric bat species

Long‐lived animals with a low annual reproductive output need a long time to recover from population crashes and are, thus, likely to face high extinction risk, if the current global environmental change will increase mortality rates. To aid conservation of those species, knowledge on the variability of mortality rates is essential. Unfortunately, however, individual‐based multiyear data sets that are required for that have only rarely been collected for free‐ranging long‐lived mammals. Here, we used a five‐year data set comprising activity data of 1,445 RFID‐tagged individuals of two long‐lived temperate zone bat species, Natterer's bats (Myotis nattereri) and Daubenton's bats (Myotis daubentonii), at their joint hibernaculum. Both species are listed as being of high conservation interest by the European Habitats Directive. Applying mixed‐effects logistic regression, we explored seasonal survival differences in these two species which differ in foraging strategy and phenology. In both species, survival over the first winter of an individual's life was much lower than survival over subsequent winters. Focussing on adults only, seasonal survival patterns were largely consistent with higher winter and lower summer survival but varied in its level across years in both species. Our analyses, furthermore, highlight the importance of species‐specific time periods for survival. Daubenton's bats showed a much stronger difference in survival between the two seasons than Natterer's bats. In one exceptional winter, the population of Natterer's bats crashed, while the survival of Daubenton's bats declined only moderately. While our results confirm the general seasonal survival pattern typical for hibernating mammals with higher winter than summer survival, they also show that this pattern can be reversed under particular conditions. Overall, our study points toward a high importance of specific time periods for population dynamics and suggests species‐, population‐, and age class‐specific responses to global climate change.     

Identification and sex determination of Bicknell's Thrushes using morphometric data

ABSTRACT The similar plumage of Bicknell's (Catharus bicknelli) and Gray‐cheeked (C. minimus) Thrushes have hindered attempts to better understand the nonbreeding biology of these species. We used morphometric data, specifically primary formulae, from Bicknell's Thrushes of known sex and age throughout their breeding range in the United States and Canada to examine possible differences between sex and age classes. We compared these data with similar data from Gray‐cheeked Thrushes in Alaska, United States and Newfoundland, Canada to examine mensural characters for distinguishing the two species. We performed a discriminant function analysis (DFA) for each age class to examine morphometric differences between male and female Bicknell's Thrushes. For second‐year (SY) and after‐second‐year (ASY) birds, wing chord was the strongest differentiator, in conjunction with tarsus length. Wing chord and tail length were used to create a discriminant function to differentiate between the two Catharus species. The discriminant functions for both age classes did not permit unambiguous separation of male and female Bicknell's Thrushes nor did the DFA enable unequivocal species identity, but most individuals were correctly classified. Significant differences in the p8–p1 measurement of Bicknell's and Gray‐cheeked Thrushes and of male and female Bicknell's Thrushes suggest that this character may be useful to augment published wing chord criteria for species identification and sex determination. Our results indicate that wing chord, in combination with tail length, is the most useful measurement for distinguishing Bicknell's from Gray‐cheeked Thrushes and, when augmented with tarsus length, to differentiate between male and female Bicknell's Thrushes outside the breeding season.     

Sillem's Mountain Finch Leucosticte sillemi is a valid species of rosefinch (Carpodacus,Fringillidae)

Sillem's Mountain Finch Leucosticte sillemi was described in 1992 on the basis of an adult and an immature specimen collected in western Tibet in September 1929, but its taxonomic validity and phylogenetic position have been unclear. Based on phylogenetic analysis of mitochondrial DNA from the holotype, we show that L. sillemi is not a colour morph of Brandt's Mountain Finch Leucosticte brandti but represents a valid, previously overlooked species of rosefinch (Carpodacus) that has secondarily acquired a pale plumage convergent on that of Leucosticte. Sillem's Mountain Finch is one of the least known species of bird and represents the only known species of rosefinch in which males have no reddish plumage coloration. This species and its sister taxon, the Tibetan Rosefinch Carpodacus roborowskii, are likely to be the world's highest‐altitude sister‐species pair of birds.     

Declining populations in one of the last refuges for threatened mammal species in northern Australia

Australia has contributed a disproportionate number of the world's mammal extinctions over the past 200 years, with the greatest loss of species occurring through the continent's southern and central arid regions. Many taxonomically and ecologically similar species are now undergoing widespread decline across the northern Australian mainland, possibly driven by predation by feral cats and changed fire regimes. Here, we report marked recent declines of native mammal species in one of Australia's few remaining areas that support an intact mammal assemblage, Melville Island, the largest island off the northern Australian coast. We have previously reported a marked decline on Melville Island of the threatened brush‐tailed rabbit‐rat (Conilurus penicillatus) over the period 2000–2015, linked to predation by feral cats. We now report a 62% reduction in small mammal trap‐success and a 36% reduction in site‐level species richness over this period. There was a decrease in trap‐success of 90% for the northern brown bandicoot (Isoodon macrourus), 64% for the brush‐tailed rabbit‐rat and 63% for the black‐footed tree‐rat (Mesembriomys gouldii), but no decline for the common brushtail possum (Trichosurus vulpecula). These results suggest that populations of native mammals on Melville Island are exhibiting similar patterns of decline to those recorded in Kakadu National Park two decades earlier, and across the northern Australian mainland more generally. Without the implementation of effective management actions, these species are likely to be lost from one of their last remaining strongholds, threatening to increase Australia's already disproportionate contribution to global mammal extinctions.     

Seasonal and annual differences in the foraging ecology of two gull species breeding in sympatry and their use of fishery discards

Niche segregation between similar species will result from an avoidance of competition but also from environmental variability, including nowadays anthropogenic activities. Gulls are among the seabirds with greater behavioural plasticity, being highly opportunistic and feeding on a wide range of prey, mostly from anthropogenic origin. Here, we analysed blood and feather stable isotopes combined with pellet analysis to investigate niche partitioning between Audouin's gull Larus audouinii and yellow‐legged gull Larus michahellis breeding in sympatry at Deserta Island, southern Portugal, during 2014 and 2015. During the breeding season there was considerable overlap in the adults’ diet, as their stable isotope values of blood and primary feather (P1) did not differ, and their pellets were comprised mainly by marine fish species. However, Audouin's gulls presented higher occurrences of pelagic fish, while yellow‐legged gulls fed more on demersal fish, insects, and refuse. SIAR mixing models also estimated a higher proportion of demersal fish in the diet of yellow‐legged gulls. We also found differences between the two gull species in chicks’ feathers, suggesting that Audouin's gull adults selected prey with lower carbon isotope values to feed their young. Secondary feather (S8) of Audouin's gull presented higher isotope values compared to yellow‐legged gulls, indicating different foraging areas (δ¹³C) and/ or trophic levels (δ¹⁵N) between the two species in the non‐breeding season. During both the all‐year and non‐breeding periods the yellow‐legged gull showed a broader isotopic niche width than Audouin's gull in 2013, and in 2014 the two gull species exhibited different isotopic niche spaces. Our study suggests that both gull species foraged in association with fisheries during the breeding season. In this sense, a discard ban implemented under the new European Union Common Fisheries Policy may lead to a food shortage, therefore future research should closely monitor the population dynamics of Audouin's and yellow‐legged gulls.     

Variation in ultraviolet reflectance by carotenoid-bearing feathers of tanagers (Thraupini: Emberizinae: Passeriformes)

Avian visual sensitivity encompasses both the human visible range (400–700 nm) and also near‐ultraviolet (UV) wavelengths (320–400 nm) invisible to normal humans. I used reflectance spectrophotometry to assess variation in UV reflectance for yellow, orange and red plumage in 67 species of tanager (Passeriformes). Previous chemical studies, and my analysis of reflectance minima, suggest that carotenoids are the dominant pigments in yellow, orange and red tanager plumage. Spectra recorded over the range of wavelengths to which birds are sensitive (320–700 nm) were invariably bimodal, with both a plateau of high reflectance at longer (> 500 nm) wavelengths and a distinct secondary peak at UV (< 400 nm) wavelengths. Within this overall framework, variation in UV reflectance was expressed within well‐defined quantitative limits: (1) peak reflectance was always lower than the corresponding plateau of reflectance at longer visible wavelengths; (2) the intensity of peak reflectance declined steadily below 350 nm; (3) wavelengths of peak reflectance clustered between 350 and 370 nm. Significant correlations were detected between various measures of total reflectance in the UV and visible wavebands, but not between various measures of spectral location of UV and visible reflectance. I propose that the strong absorption band at short visible wavelengths (～ 380–550 nm) responsible for bimodal spectra of carotenoids in vitro is also responsible for bimodal reflectance by carotenoid‐based plumage colours. The construction of the UV and visible reflectance bands from different sides of this same absorbance band provides a mechanism for the observed covariation between UV and visible wavelengths. Lack of an association between the spectral locations of the UV and visible reflectance bands may result from the limited variation in spectral location of the UV band. These patterns suggest that plumage colours are subject to constraints, just as are more traditional morphological characters. © 2005 The Linnean Society of London, Biological Journal of the Linnean Society, 2005, 84 , 243–257.     

Community‐level effects of herbicide‐based restoration treatments: structural benefits but at what cost?

Invasive species alter ecosystem structure, impact biodiversity, and have significant economic costs. In Oregon's Willamette Valley, invasive grasses Arrhenatherum elatius and Schedonorus arundinaceus alter the dynamics of the phenologically paired interaction between an endangered butterfly, Icaricia icarioides fenderi (Fender's blue), and its larval host plant, Lupinus oreganus (Kincaid's lupine). To test methods to restore this interaction, we established a 3‐year experiment where a post‐emergent grass‐specific herbicide, fluazifop‐p‐butyl, was applied to Fender's blue habitat. Plant community data were recorded throughout the growing season at eight paired plots for 1 year prior to treatment and 3 years during treatment. We asked whether annual application of herbicide could reduce the height of invasive grasses to levels at or beneath the height of Kincaid's lupine racemes throughout the Fender's blue flight season. We hypothesized that native forb species, which are critical nectar sources for Fender's blue, would increase in cover and frequency following the release from competitive dominance of invasive grasses. Grass‐specific herbicide reduced grass height during the flight season of Fender's blue, but with several costs. We found no change in nectar and a suppression of lupine growth in plots in response to experimental herbicide treatment. Each study site had multiple secondary invaders; the long‐term impact of these new invaders is unknown. We suggest that herbicide application results in a net negative effect in the context of Fender's blue habitat restoration. That is, the costs to primary resources for Fender's blue and the influx of secondary invaders may be as problematic as the primary invasion by non‐native grasses.     

Trail‐sharing among tropical ants: interspecific use of trail pheromones?

1. Trail‐sharing between different ant species is rare and restricted to a small number of species pairs. Its underlying mechanisms are largely unknown. For trail‐sharing to occur, two factors are required: (i) one or both species must recognise the other species or its pheromone trails and (ii) both species must tolerate each other to a certain extent to allow joint use of the trail. A species that follows another's trails can efficiently exploit the other's information on food sources contained in the pheromone trails. Hence, food competition and thus aggressive interactions between a species following another's trail and the species being followed, seem likely. 2. In the present study, we investigated interspecific trail following and interspecific aggression in trail sharing associations (i) among Polyrhachis ypsilon, Camponotus saundersi, and Dolichoderus cuspidatus, and (ii) among Camponotus rufifemur and Crematogaster modiglianii. We tested whether trail‐sharing species follow each other's pheromone trails, and whether the ants tolerated or attacked their trail‐sharing partners. In both associations, we confronted workers with pheromone trails of their associated species, and, for the former association, measured interspecific aggression among the trail‐sharing species. 3. In our assays, D. cuspidatus and C. rufifemur regularly followed heterospecific pheromone trails of P. ypsilon and C. modiglianii, respectively. However, only few workers of the remaining species followed heterospecific pheromone trails. Thus, shared trails of P. ypsilon and C. saundersi cannot be explained by interspecific trail‐following. 4. Interspecific aggression among P. ypsilon, C. saundersi, and D. cuspidatus was strongly asymmetric, C. saundersi being submissive to the other two. All three species differentiated between heterospecific workers from the same or another site, suggesting habituation to the respective trail‐sharing partners. We therefore hypothesise that differential tolerance by dominant ant species may be mediated by selective habituation towards submissive species and this way determines the assembly of trail‐sharing associations.     

Monteiro's Storm‐petrel Oceanodroma monteiroi: a new species from the Azores

The existence of two seasonally distinct breeding populations of Oceanodroma storm‐petrels in the Azores islands was first documented in 1996. The discovery of morphological differences between the populations led to the suggestion that they may represent cryptic sibling species. Recent mtDNA and microsatellite analysis from storm‐petrel populations has considerably advanced our understanding of their taxonomic relationships. Here we present new information on the timing of breeding and moult of the two Azores populations, the extent of exchange of individuals between seasons, and diet from feather isotopes. We conclude that the hot‐season Azores population should be considered a new species for which we propose the name Oceanodroma monteiroi, Monteiro's Storm‐petrel. The species is both genetically distinct and genetically isolated from the sympatric cool‐season population of Madeiran Storm‐petrel Oceanodroma castro, and from all other populations of Oceanodroma castro in the Atlantic and Pacific Oceans examined to date. Differences in the vocalizations permit species recognition, and the extent of primary feather wear and stage of moult aids separation of the two species in the Azores, which is especially valuable during August when both attend the breeding colonies in large numbers. Feather carbon and nitrogen isotopes reveal that the diet of Monteiro's Storm‐petrel differs from that of the sympatric Madeiran Storm‐petrel during both breeding and non‐breeding seasons, and unlike the Madeiran Storm‐petrel, Monteiro's Storm‐petrel appears to maintain the same foraging environment during the summer and winter months, though it shows a dietary shift to higher trophic levels during the non‐breeding season. Monteiro's Storm‐petrel is thought to be confined to the Azores archipelago, where it is currently known to nest on just two small neighbouring islets. The total population size was estimated at 250–300 pairs in 1999.     

Implications of mitochondrial DNA polyphyly in two ecologically undifferentiated but morphologically distinct migratory birds, the masked and white-browed woodswallows Artamus spp. of inland Australia

The white‐browed woodswallow Artamus superciliosus and masked woodswallow A. personatus (Passeriformes: Artamidae) are members of Australia's diverse arid‐ and semi‐arid zone avifauna. Widely sympatric and among Australia's relatively few obligate long‐distance temperate‐tropical migrants, the two are well differentiated morphologically but not ecologically and vocally. They are pair breeders unlike other Artamus species, which are at least facultative cooperative breeders. For these reasons they are an excellent case in which to use molecular data in integrative study of their evolution from ecological and biogeographical perspectives. We used mitochondrial DNA (mtDNA) to test whether they are each other's closest relatives, whether they evolved migration independently, whether they have molecular signatures of population expansions like some other Australian arid zone birds, and to estimate the timing of any inferred population expansions. Their mtDNAs are monophyletic with respect to other species of Artamus but polyphyletic with respect to each other. The two species appear not to have evolved migration independently of each other but their morphological and mtDNA evolution have been strongly decoupled. Some level of hybridization and introgression cannot be dismissed outright as being involved in their mtDNA polyphyly but incomplete sorting of their most recent common ancestor's mtDNA is a simpler explanation consistent with their ecology. Bayesian phylogenetic inference and analyses of diversity within the two species (n=77) with conventional diversity statistics, statistical parsimony, and tests for population expansion vs stability (Tajima's D, Fu's Fs and Ramos‐Onsin and Rozas's R₂) all favour recent population increases. However, a non‐starlike network suggests expansion(s) relatively early in the Pleistocene. Repeated population bottlenecks corresponding with multiple peaks of Pleistocene aridity could explain our findings, which add a new dimension to accruing data on the effects of Pleistocene aridity on the Australian biota.     

Structure and composition of grassland habitats used by wintering Smith's Longspurs: the importance of native grasses

ABSTRACT Smith's Longspurs (Calcarius pictus) are a species of concern in North America because of their limited range and apparent low population size. To better understand winter habitat needs and guide management of this species, we examined habitat associations of Smith's Longspurs in eastern Arkansas by comparing grassland patches where Smith's Longspurs flushed to randomly located patches in the same area. Smith's Longspurs were found in sparse grassland patches of relatively low height adjacent to airport runways where the native grass prairie three‐awn (Aristida oligantha) dominated ground cover and vertical structure. Smith's Longspurs were not found in vegetation plots dominated by non‐native Bermuda grass (Cynodon dactylon). Prairie three‐awn grass may provide concealment from predators and their seeds may be an important food source. Occurrence of Smith's Longspurs was also correlated with less litter, perhaps because deeper litter could make walking and searching for seeds more difficult. Availability of suitable habitat for Smith's Longspurs along airport runways may be declining due to natural succession of grassland habitat in the absence of disturbance and recent changes in management that favor Bermuda grass. Conversion and degradation of native prairie has resulted in the decline in abundance and distribution of Chestnut‐collared Longspurs (C. ornatus) and McCown's Longspurs (Rhynchophanes mccownii). Our findings suggest that conversion of native grasslands to non‐native grasslands results in loss and degradation of habitat for wintering populations of Smith's Longspurs.     

Diversification across the Palaearctic desert belt throughout the Pleistocene: phylogeographic history of the Houbara–Macqueen's bustard complex (Otididae: Chlamydotis) as revealed by mitochondrial DNA

Studies on the influence of Pleistocene climatic fluctuations and associated habitat changes on arid‐adapted bird species living in the Holarctic region are comparatively rare. In contrast to temperate species, the populations of arid‐adapted avian species might be characterized by low genetic differentiation because periods of population isolation were associated with the short interglacial periods, while population expansion events might have occurred during the longer glacial periods when steppe‐like vegetation might have been prevalent. In this study, we tested this hypothesis in a widespread arid‐adapted taxon of the Palaearctic desert belt, the Houbara–Macqueen's bustard complex. The later includes the Houbara bustard Chlamydotis undulata, comprising the North African subspecies Chlamydotis u. undulata and Chlamydotis u. fuertaventurae from the Canary Islands, and the Asian Macqueen's bustard Chlamydotis macqueenii. A long fragment (1042 bp) of the Cyt‐b gene was investigated in 39 representatives of the two species to assess phylogenetic and phylogeographic patterns, and demographic history and to compute divergence time estimates using a Bayesian relaxed molecular clock approach based on different coalescent priors. While the two species are genetically distinct, we found little intraspecific genetic differentiation. The divergence time of the two species falls within a period of extreme aridity at around 0.9 million years ago, which most likely resulted in an east–west vicariance along the Arabo‐Saharan deserts. Differentiation within Houbara and Macqueen's bustard occurred later during the Middle to Upper Pleistocene, and as we have predicted, periods of range expansion were associated to the last glacial period at least in the Macqueen's bustard.     

Wintering hummingbirds in Alabama and Florida: species diversity, sex and age ratios, and site fidelity

ABSTRACT Over the past several decades, there have been numerous reports of hummingbirds wintering in the southeastern United States. However, little is known about the species present and their relative abundance. From November 1998 to March 2008, we examined the species diversity, sex and age ratios, and site fidelity of hummingbirds wintering in southern Alabama and northern Florida. We captured and banded 1598 individuals representing 10 species, and the most frequently captured species were Rufous Hummingbirds (Selasphorus rufus; 51.6%), Ruby‐throated Hummingbirds (Archilochus colubris; 23.5%), and Black‐chinned Hummingbirds (Archilochus alexandri; 16.9%). Other species captured included Buff‐bellied Hummingbirds (Amazilia yucatanensis), Calliope Hummingbirds (Stellula calliope), Allen's Hummingbirds (Selasphorus sasin), Broad‐tailed Hummingbirds (Selasphorus platycercus), Broad‐billed Hummingbirds (Cynanthus latirostris), Anna's Hummingbirds (Calypte anna), and Costa's Hummingbirds (Calypte costae). Most hummingbirds (71.8%) were captured in December and January. For most species, sex ratios were male‐biased for juveniles and female‐biased for adults, indicating possible differential mortality. Of 1598 hummingbirds captured, 144 representing five species returned to the same wintering location at least once. Female Rufous Hummingbirds (20.4% of individuals captured) exhibited the greatest site fidelity. Recaptures of banded Rufous Hummingbirds in autumn and early winter revealed that some individuals moved south into Alabama or Florida from Tennessee, northern Georgia, and northern Louisiana. Same‐season recaptures of banded Rufous Hummingbirds suggest that their spring migration route is west along the Gulf Coast. Our results suggest that Alabama and Florida are viable overwintering areas for several species of hummingbirds, with numbers of species and individuals higher than previously recognized. However, more study is needed to confirm migration routes and to determine if Ruby‐throated Hummingbirds wintering in our study area are year‐round residents or migrants.     

Pollinator specialization increases with a decrease in a mass‐flowering plant in networks inferred from DNA metabarcoding

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Naturalizing non-local native trees at Botany Bay: The long-term impact of historical plantings

Non‐local ‘native’ species used in historical plantings at Captain Cook's Landing Place are spreading into bushland. What can we learn from the long‐term impact of this site's well‐intentioned but ecologically inappropriate plantings?     

Prey preferences of free‐ranging cheetahs on farmland: scat analysis versus farmers' perceptions

Human–predator conflict is one of the biggest threats to large carnivore species worldwide. Its intensity is closely linked to farmer's attitudes and perceptions of predators. As a result, farmers' estimates of the number of livestock or game‐stock animals killed by predators are often formed based on the perceived number of predators present and their perceivably favoured prey species. This study aims to examine the prey preferences of cheetahs Acinonyx jubatus in relation to farmers' perceptions and the relative contribution of livestock and game‐stock to the cheetahs' diet. Cheetahs' prey preferences were determined through the cross‐sectional analysis of prey hair, found in cheetah scat. Cheetahs were found to predominantly prey on free‐ranging abundant game species, primarily kudu Tragelaphus strepsiceros. Game ranchers overestimated the prominence of game‐stock to the cheetahs' diet, especially springbok Antidorcas marsupialis. Potential reasons for these discrepancies and the importance of abundant natural prey as a potential human–predator coexistence strategy are discussed.