Abstract: "The interaction of gradual climate trends and extreme weather events since the turn of the century has triggered complex and, in some cases, catastrophic ecological responses around the world. We illustrate this using Australian examples within a press–pulse framework. Despite the Australian biota being adapted to high natural climate variability, recent combinations of climatic presses and pulses have led to population collapses, loss of relictual communities and shifts into novel ecosystems. These changes have been sudden and unpredictable, and may represent permanent transitions to new ecosystem states without adaptive management interventions. The press–pulse framework helps illuminate biological responses to climate change, grounds debate about suitable management interventions and highlights possible consequences of (non-) intervention."
08 July 2018
Abstract: "Researchers have created hybrid rhino embryos as part of a 'Hail-Mary' attempt to rescue the northern white rhinoceros from all but certain extinction. The embryos — which have now been frozen — contain DNA from northern white rhinos (Ceratotherium simum cottoni) and a close relative subspecies and could be implanted into surrogates to yield animals that are a mix of both. The work is reported in a Nature Communications paper published on 4 July. The research “is an impressive step forward for the whole field”, says stem-cell biologist Jeanne Loring, at the Scripps Research Institute in La Jolla, California. Her team hopes to use stem-cell technology to repopulate the rhinos."
18 June 2018
Ambitious targets for the retention — not just formal protection — of nature are urgently needed to conserve biodiversity and to maintain crucial ecosystem services for humanity.
Natural re-colonization and admixture of wolves (Canis lupus) in the US Pacific Northwest: challenges for the protection and management of rare and endangered taxa
Abstract: "Admixture resulting from natural dispersal processes can potentially generate novel phenotypic variation that may facilitate persistence in changing environments or result in the loss of population-specific adaptations. Yet, under the US Endangered Species Act, policy is limited for management of individuals whose ancestry includes a protected taxon; therefore, they are generally not protected under the Act. This issue is exemplified by the recently re-established grey wolves of the Pacific Northwest states of Washington and Oregon, USA. This population was likely founded by two phenotypically and genetically distinct wolf ecotypes: Northern Rocky Mountain (NRM) forest and coastal rainforest. The latter is considered potentially threatened in southeast Alaska and thus the source of migrants may affect plans for their protection. To assess the genetic source of the re-established population, we sequenced a ~ 300 bp portion of the mitochondrial control region and ~ 5 Mbp of the nuclear genome. Genetic analysis revealed that the Washington wolves share ancestry with both wolf ecotypes, whereas the Oregon population shares ancestry with NRM forest wolves only. Using ecological niche modelling, we found that the Pacific Northwest states contain environments suitable for each ecotype, with wolf packs established in both environmental types. Continued migration from coastal rainforest and NRM forest source populations may increase the genetic diversity of the Pacific Northwest population. However, this admixed population challenges traditional management regimes given that admixture occurs between an adaptively distinct ecotype and a more abundant reintroduced interior form. Our results emphasize the need for a more precise US policy to address the general problem of admixture in the management of endangered species, subspecies, and distinct population segments."
Abstract: "Recent large-scale analyses suggest that local management actions may not protect coral reefs from climate change, yet most local threat-reduction strategies have not been tested experimentally. We show that removing coral predators is a common local action used by managers across the world, and that removing the corallivorous snail Coralliophila abbreviata from Caribbean brain corals (Pseudodiploria and Diploria species) before a major warming event increased coral resilience by reducing bleaching severity (resistance) and post-bleaching tissue mortality (recovery). Our results highlight the need for increased evaluation and identification of local interventions that improve coral reef resilience."
11 May 2018
Abstract: "Marine protected areas (MPAs) are a primary management tool for mitigating threats to marine biodiversity1,2. MPAs and the species they protect, however, are increasingly being impacted by climate change. Here we show that, despite local protections, the warming associated with continued business-as-usual emissions (RCP8.5)3 will likely result in further habitat and species losses throughout low-latitude and tropical MPAs4,5. With continued business-as-usual emissions, mean sea-surface temperatures within MPAs are projected to increase 0.035 °C per year and warm an additional 2.8 °C by 2100. Under these conditions, the time of emergence (the year when sea-surface temperature and oxygen concentration exceed natural variability) is mid-century in 42% of 309 no-take marine reserves. Moreover, projected warming rates and the existing ‘community thermal safety margin’ (the inherent buffer against warming based on the thermal sensitivity of constituent species) both vary among ecoregions and with latitude. The community thermal safety margin will be exceeded by 2050 in the tropics and by 2150 for many higher latitude MPAs. Importantly, the spatial distribution of emergence is stressor-specific. Hence, rearranging MPAs to minimize exposure to one stressor could well increase exposure to another. Continued business-as-usual emissions will likely disrupt many marine ecosystems, reducing the benefits of MPAs."
19 April 2018
Freshwater fish diversity is harmed as much by selective logging in rainforests as they are by complete deforestation, according to a new study.
Researchers had expected the level of damage would rise depending on the amount of logging and were surprised to discover the impact of removing relatively few trees.