Cold comfort: Arctic seabirds find refugia from climate change and potential competition in marginal ice zones and fjords

AbstractClimate change alters species distributions by shifting their fundamental niche in space through time. Such effects may be exacerbated by increased inter-specific competition if climate alters species dominance where competitor ranges overlap. This study used census data, telemetry and stable isotopes to examine the population and foraging ecology of a pair of Arctic and temperate congeners across an extensive zone of sympatry in Iceland, where sea temperatures varied substantially. The abundance of Arctic Brünnich’s guillemot Uria lomvia declined with sea temperature. Accessibility of refugia in cold water currents or fjords helped support higher numbers and reduce rates of population decline. Competition with temperate Common guillemots Uria aalge did not affect abundance, but similarities in foraging ecology were sufficient to cause competition when resources are limiting. Continued warming is likely to lead to further declines of Brünnich’s guillemot, with implications for conservation status and ecosystem services.

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A globally threatened shark, Carcharias taurus, shows no population decline in South Africa

Scientific Reports ◽

10.1038/s41598-020-75044-2 ◽

2020 ◽

Vol 10 (1) ◽

Author(s):

Juliana D. Klein ◽

Aletta E. Bester-van der Merwe ◽

Matthew L. Dicken ◽

Arsalan Emami-Khoyi ◽

Kolobe L. Mmonwa ◽

...

Keyword(s):

South Africa ◽

Census Data ◽

Demographic History ◽

Conservation Status ◽

Population Decline ◽

Multilocus Genotype ◽

Population Declines ◽

Effective Population ◽

Anthropogenic Pressures ◽

Carcharias Taurus

Abstract Knowledge about the demographic histories of natural populations helps to evaluate their conservation status, and potential impacts of natural and anthropogenic pressures. In particular, estimates of effective population size obtained through molecular data can provide useful information to guide management decisions for vulnerable populations. The spotted ragged-tooth shark, Carcharias taurus (also known as the sandtiger or grey nurse shark), is widely distributed in warm-temperate and subtropical waters, but has suffered severe population declines across much of its range as a result of overexploitation. Here, we used multilocus genotype data to investigate the demographic history of the South African C. taurus population. Using approximate Bayesian computation and likelihood-based importance sampling, we found that the population underwent a historical range expansion that may have been linked to climatic changes during the late Pleistocene. There was no evidence for a recent anthropogenic decline. Together with census data suggesting a stable population, these results support the idea that fishing pressure and other threats have so far not been detrimental to the local C. taurus population. The results reported here indicate that South Africa could possibly harbour the last remaining, relatively pristine population of this widespread but vulnerable top predator.

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Climate causes shifts in grey seal phenology by modifying age structure

Proceedings of The Royal Society B Biological Sciences ◽

10.1098/rspb.2021.2284 ◽

2021 ◽

Vol 288 (1964) ◽

Author(s):

James C. Bull ◽

Owen R. Jones ◽

Luca Börger ◽

Novella Franconi ◽

Roma Banga ◽

...

Keyword(s):

Climate Change ◽

Age Structure ◽

Census Data ◽

Age Distribution ◽

Population Level ◽

Ecosystem Change ◽

Population Census ◽

Sea Temperature ◽

Population Age Structure ◽

Phenological Shifts

There are numerous examples of phenological shifts that are recognized both as indicators of climate change and drivers of ecosystem change. A pressing challenge is to understand the causal mechanisms by which climate affects phenology. We combined annual population census data and individual longitudinal data (1992–2018) on grey seals, Halicheorus grypus , to quantify the relationship between pupping season phenology and sea surface temperature. A temperature increase of 2°C was associated with a pupping season advance of approximately seven days at the population level. However, we found that maternal age, rather than sea temperature, accounted for changes in pupping date by individuals. Warmer years were associated with an older average age of mothers, allowing us to explain phenological observations in terms of a changing population age structure. Finally, we developed a matrix population model to test whether our observations were consistent with changes to the stable age distribution. This could not fully account for observed phenological shift, strongly suggesting transient modification of population age structure, for example owing to immigration. We demonstrate a novel mechanism for phenological shifts under climate change in long-lived, age- or stage-structured species with broad implications for dynamics and resilience, as well as population management.

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Increasing temperature threatens an already endangered coastal dune plant

10.1101/2020.08.02.233288 ◽

2020 ◽

Author(s):

Aldo Compagnoni ◽

Eleanor Pardini ◽

Tiffany M. Knight

Keyword(s):

Climate Change ◽

Conservation Status ◽

Population Decline ◽

Species Conservation ◽

Coastal Dune ◽

Population Growth Rates ◽

Data Intensive ◽

Climate Change Effects ◽

The Usa ◽

Dune Plant

ABSTRACTClimate change has the potential to reduce the abundance and distribution of species and threaten global biodiversity, but it is typically not listed as a threat in classifying species conservation status. This likely occurs because demonstrating climate change as a threat requires data-intensive demographic information. Moreover, the threat from climate change is often studied in specific biomes, such as polar or arid ones. Other biomes, such as coastal ones, have received little attention, despite being currently exposed to substantial climate change effects. We forecast the effect of climate change on the demography and population size of a federally endangered coastal dune plant (Lupinus tidestromii). We use data from a 14-year demographic study across seven extant populations of this endangered plant. Using model selection, we found that survival and fertility measures responded negatively to temperature anomalies. We then produced forecasts based on stochastic individual based population models that account for uncertainty in demographic outcomes. Despite large uncertainties, we predict that all populations will decline if temperatures increase by 1° Celsius. Considering the total number of individuals across all seven populations, the most likely outcome is a population decline of 90%. Moreover, we predict extinction is certain for one of our seven populations. These results demonstrate that climate change will profoundly decrease the current and future population growth rates of this plant, and its chance of persistence. Thus, our study provides the first evidence that climate change is an extinction threat for a plant species classified as endangered under the USA Endangered Species Act.

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The Bramble Cay melomys Melomys rubicola (Rodentia : Muridae): a first mammalian extinction caused by human-induced climate change?

Wildlife Research ◽

10.1071/wr16157 ◽

2017 ◽

Vol 44 (1) ◽

pp. 9 ◽

Cited By ~ 25

Author(s):

Natalie L. Waller ◽

Ian C. Gynther ◽

Alastair B. Freeman ◽

Tyrone H. Lavery ◽

Luke K.-P. Leung

Keyword(s):

Climate Change ◽

Sea Level Rise ◽

Sea Level ◽

Captive Breeding ◽

Conservation Status ◽

Population Decline ◽

Food Resource ◽

Storm Surges ◽

Water Levels ◽

Anthropogenic Climate Change

Aims Sea-level rise is one of the most certain consequences of global warming and is predicted to exert significant adverse effects on wildlife in coastal habitats worldwide. Terrestrial fauna inhabiting low-lying islands are likely to suffer the greatest loss to habitat from sea-level rise and other oceanographic impacts stemming from anthropogenic climate change. Bramble Cay (Maizab Kaur), an ~4ha, low elevation sand cay located in Torres Strait, Australia, supports the only known population of the endangered Bramble Cay melomys Melomys rubicola Thomas, 1924. As a result of a decline in this population noted during previous monitoring to 2004, habitat loss due to erosion of the cay and direct mortality from storm surges were implicated as major threats to this species. This study aimed to confirm the current conservation status of the species, to seek information about the key factor or factors responsible for the population decline and to recover any remaining individuals for a captive insurance population. Methods During three survey periods (December 2011, March 2014 and August–September 2014), a total of 1170 small mammal trap-nights, 60 camera trap-nights, 5h of nocturnal searches and 5h of diurnal searches were undertaken on Bramble Cay. Key results All three survey periods failed to detect any Bramble Cay melomys. The island had experienced a recent, severe reduction in vegetation, which is the primary food resource for the Bramble Cay melomys. Herbaceous cover on the cay decreased from 2.16ha in 2004 to 0.065ha in March 2014 before recovering somewhat to 0.19ha in August–September 2014. Conclusions These results demonstrate that this rodent species has now been extirpated on Bramble Cay. The vegetation decline was probably due to ocean inundation resulting from an increased frequency and intensity of weather events producing extreme high water levels and storm surges, in turn caused by anthropogenic climate change. Implications The loss of the Bramble Cay melomys from Bramble Cay probably represents the first documented mammalian extinction due to human-induced climate change. This event highlights the immediate need to mitigate predicted impacts of sea-level rise and ocean inundation on other vulnerable species occurring on low lying islands and in susceptible coastal zones through captive breeding and reintroduction or other targeted measures.

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A globally threatened shark, Carcharias taurus, shows no population decline in South Africa

10.1101/2020.06.02.130005 ◽

2020 ◽

Author(s):

Juliana D. Klein ◽

Aletta E. Bester-van der Merwe ◽

Matthew L. Dicken ◽

Arsalan Emami-Khoyi ◽

Kolobe L. Mmonwa ◽

...

Keyword(s):

South Africa ◽

Census Data ◽

Demographic History ◽

Conservation Status ◽

Population Decline ◽

Multilocus Genotype ◽

Population Declines ◽

Effective Population ◽

Anthropogenic Pressures ◽

Carcharias Taurus

AbstractKnowledge about the demographic histories of natural populations helps to evaluate their conservation status, and potential impacts of natural and anthropogenic pressures. In particular, estimates of effective population size obtained through molecular data can provide useful information to guide management decisions for vulnerable populations. The spotted ragged-tooth shark Carcharias taurus (also known as the sandtiger or grey nurse shark) is widely distributed in warm-temperate and subtropical waters, but has suffered severe population declines across much of its range as a result of overexploitation. Here, we used multilocus genotype data to investigate the demographic history of the South African C. taurus population. Using approximate Bayesian computation and likelihood-based importance sampling, it was found that the population underwent a historical range expansion that may have been linked to climatic changes during the late Pleistocene. There was no evidence for a recent anthropogenic decline. Together with census data suggesting a stable population, these results support the idea that fishing pressure and other threats have so far not been detrimental to the local C. Taurus population. The results reported here indicate that South Africa could possibly harbour the last remaining, relatively pristine population of this widespread but vulnerable top predator.

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Orchestrated Flowering and Interspecific Facilitation: Key Factors in the Maintenance of the Main Pollinator of Coexisting Threatened Species of Andean Wax Palms (Ceroxylon spp.)

Annals of the Missouri Botanical Garden ◽

10.3417/2020590 ◽

2020 ◽

Vol 105 (3) ◽

pp. 281-299

Author(s):

Javier Carreño-Barrera ◽

Luis Alberto Núñez-Avellaneda ◽

Maria José Sanín ◽

Artur Campos D. Maia

Keyword(s):

Conservation Status ◽

Population Decline ◽

Floral Biology ◽

Fruit Production ◽

Biological Data ◽

Fruit Yield ◽

Insect Species ◽

Individual Species ◽

Pollination Services ◽

Flower Visiting

Solitary, dioecious, and mostly endemic to Andean cloud forests, wax palms (Ceroxylon Bonpl. ex DC. spp.) are currently under worrisome conservation status. The establishment of management plans for their dwindling populations rely on detailed biological data, including their reproductive ecology. As in the case of numerous other Neotropical palm taxa, small beetles are assumed to be selective pollinators of wax palms, but their identity and relevance in successful fruit yield were unknown. During three consecutive reproductive seasons we collected data on population phenology and reproductive and floral biology of three syntopic species of wax palms native to the Colombian Andes. We also determined the composition of the associated flower-visiting entomofauna, quantifying the extent of the role of individual species as effective pollinators through standardized value indexes that take into consideration abundance, constancy, and pollen transport efficiency. The studied populations of C. parvifrons (Engel) H. Wendl., C. ventricosum Burret, and C. vogelianum (Engel) H. Wendl. exhibit seasonal reproductive cycles with marked temporal patterns of flower and fruit production. The composition of the associated flower-visiting entomofauna, comprised by ca. 50 morphotypes, was constant across flowering seasons and differed only marginally among species. Nonetheless, a fraction of the insect species associated with pistillate inflorescences actually carried pollen, and calculated pollinator importance indexes demonstrated that one insect species alone, Mystrops rotundula Sharp, accounted for 94%–99% of the effective pollination services for all three species of wax palms. The sequential asynchronous flowering of C. parvifrons, C. ventricosum, and C. vogelianum provides an abundant and constant supply of pollen, pivotal for the maintenance of large populations of their shared pollinators, a cooperative strategy proven effective by high fruit yield rates (up to 79%). Reproductive success might be compromised for all species by the population decline of one of them, as it would tamper with the temporal orchestration of pollen offer.

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Turbid Coral Reefs: Past, Present and Future—A Review

Diversity ◽

10.3390/d13060251 ◽

2021 ◽

Vol 13 (6) ◽

pp. 251

Author(s):

Adi Zweifler (Zvifler) ◽

Michael O’Leary ◽

Kyle Morgan ◽

Nicola K. Browne

Keyword(s):

Climate Change ◽

Coral Reef ◽

Coral Reefs ◽

Environmental Change ◽

Scientific Literature ◽

Conservation Status ◽

Climate Change Impacts ◽

Geographic Range ◽

Reef Complex ◽

Sediment Input

Increasing evidence suggests that coral reefs exposed to elevated turbidity may be more resilient to climate change impacts and serve as an important conservation hotspot. However, logistical difficulties in studying turbid environments have led to poor representation of these reef types within the scientific literature, with studies using different methods and definitions to characterize turbid reefs. Here we review the geological origins and growth histories of turbid reefs from the Holocene (past), their current ecological and environmental states (present), and their potential responses and resilience to increasing local and global pressures (future). We classify turbid reefs using new descriptors based on their turbidity regime (persistent, fluctuating, transitional) and sources of sediment input (natural versus anthropogenic). Further, by comparing the composition, function and resilience of two of the most studied turbid reefs, Paluma Shoals Reef Complex, Australia (natural turbidity) and Singapore reefs (anthropogenic turbidity), we found them to be two distinct types of turbid reefs with different conservation status. As the geographic range of turbid reefs is expected to increase due to local and global stressors, improving our understanding of their responses to environmental change will be central to global coral reef conservation efforts.

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Combining conservation status and species distribution models for planning assisted colonisation under climate change

Journal of Ecology ◽

10.1111/1365-2745.13606 ◽

2021 ◽

Author(s):

Gabriele Casazza ◽

Thomas Abeli ◽

Gianluigi Bacchetta ◽

Davide Dagnino ◽

Giuseppe Fenu ◽

...

Keyword(s):

Climate Change ◽

Species Distribution ◽

Species Distribution Models ◽

Conservation Status ◽

Distribution Models

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Oxythermal habitat as a primary driver of ecological niche and genetic diversity in cisco (Coregonus artedi)

Canadian Journal of Fisheries and Aquatic Sciences ◽

10.1139/cjfas-2021-0059 ◽

2021 ◽

Author(s):

Ryan C Grow ◽

Kyle D Zimmer ◽

Jennifer L Cruise ◽

Simon K Emms ◽

Loren M Miller ◽

...

Keyword(s):

Climate Change ◽

Genetic Diversity ◽

Dissolved Oxygen ◽

Cold Water ◽

Global Scale ◽

Isotopic Niche ◽

Coregonus Artedi ◽

Primary Driver ◽

Water Species ◽

Cold Water Species

Cisco (Coregonus artedi) are threatened by climate change and lake eutrophication, and their oxythermal habitat can be assessed with TDO3, the water temperature at which dissolved oxygen equals 3 mg L-1. We assessed the influence of TDO3 on cisco habitat use, genetic diversity, diets, and isotopic niche in 32 lakes ranging from oligotrophic to eutrophic. Results showed that as TDO3 increased cisco were captured higher in the water column, in a narrower band, with higher minimum temperatures and lower minimum dissolved oxygen. TDO3 was also negatively related to cisco allelic richness and expected heterozygosity, likely driven by summer kill events. Moreover, TDO3 influenced the isotopic niche of cisco, as fish captured deeper were more depleted in δ13C and more enriched in δ15N compared to epilimnetic baselines. Lastly, cisco in high TDO3 lakes consumed more Daphnia, had fewer empty stomachs, and achieved larger body size. Our work identifies specific characteristics of cisco populations that respond to climate change and eutrophication effects, and provides a framework for understanding responses of other cold-water species at the global scale.

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A multiproxy reconstruction of vegetation dynamics in the Eastern Alps (Switzerland): combining paleoecological and paleogenetic approaches.

10.5194/egusphere-egu21-14457 ◽

2021 ◽

Author(s):

Laura Dziomber ◽

Lisa Gurtner ◽

Maria Leunda ◽

Christoph Schwörer

Keyword(s):

Climate Change ◽

Ancient Dna ◽

Vegetation Dynamics ◽

Population Decline ◽

Future Climate ◽

Ice Age ◽

Future Climate Change ◽

The Holocene ◽

Plant Remains ◽

The Impact

Current and future climate change is a serious threat to biodiversity and ecosystem stability. With a rapid increase of global temperatures by 1.5&#176;C since the pre-industrial period and a projected warming of 1.5-4&#176;C by the end of this century, plant species are forced to either adapt to these changes, shift their distribution range to higher elevation, or face population decline and extinction. Today, there is an urgent need to better understand the responses of mountain vegetation to climate change in order to predict the consequences of the human-driven global change currently occurring during the Anthropocene and maintain species diversity and ecosystem services. However, most predictions are based on short-term experiments. There is, in general, an insufficient use of longer time scales in conservation biology to understand long-term processes. Palaeoecological data are a great source of information to infer past species responses to changing environmental factors, such as climate or anthropogenic disturbances.The last climate change of a similar magnitude and rate as projected for this century was the transition between the last Ice Age and the Holocene interglacial (ca. 11,700 years ago). By analyzing subfossil plant remains such as plant macrofossils, charcoal and pollen from natural archives, we can study past responses to climate change. However, until recently it was not possible to reconstruct changes at the population level. With the development of new methods to extract ancient DNA (aDNA) from plant remains and next generation DNA-sequencing techniques, we can now infer past population dynamics by analyzing the genetic variation through time. Ancient DNA might also be able to reveal if species could adapt to climatic changes by identifying intraspecific variation of specific genes related to climatic adaptations.We are currently investigating a palaeoecological archive from a high-altitude mountain lake, Lai da Vons (1991 m a.s.l), situated in Eastern Switzerland. We are presenting preliminary macrofossil, pollen and charcoal results to reconstruct local to regional vegetation and fire dynamics with high chronological precision and resolution. In a next step, we will use novel molecular methods, in order to track adaptive and neutral genetic diversity through the Holocene by analyzing aDNA from subfossil conifer needles. The overarching goal of this large-scale, multiproxy study is to better understand past vegetation dynamics and the impact of future climate change on plants at multiple scales; from the genetic to the community level.&#160;

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