Malin L. Pinsky’s research while affiliated with University of California, Santa Cruz and other places

Humans have transformed ecosystems through habitat modification, harvesting, species introduction, and climate change. Changes in species distribution and composition are often thought to induce biotic homogenization, defined as a decline in spatial beta diversity through time. However, it is unclear whether homogenization is common in ocean ecosystems and if changes in beta diversity exhibit linear or more complex dynamics. Here, we assessed patterns of homogenization or its converse (differentiation) across more than 175,000 samples of 2,006 demersal fish species from 34 regions spanning six decades and 20% of the planet’s continental shelf area. While ten regions (29%) recorded significant homogenization, eleven (32%) recorded significant differentiation. Non-monotonic temporal fluctuations in beta diversity occurred in 15 regions, highlighting complex dynamics missed by before-and-after snapshots that can drive spurious conclusions about trends in beta diversity. Fishing pressure and temperature helped explain variance in beta diversity across years and regions. However, the strength and direction of these effects differed by region. Here we showed that, despite intense anthropogenic impacts on the oceans, the majority of demersal marine fish communities do not follow the global homogenization paradigm common in other realms.

Population dynamic models are widely used to predict demography. However, they have rarely been extended to biogeographical applications despite widespread calls to do so. We developed a process-based dynamic range model (DRM) that estimated demographic rates and the effects of the environment on demographic rates to forecast species range shifts in response to temperature change. As a proof of concept, we fitted DRMs to historical observations of summer flounder (Paralichthys dentatus), a fish species in the Northwest Atlantic, and evaluated model skill at retrospective forecasting. The best DRMs outperformed a statistical species distribution model and a persistence forecast at predicting biogeographical dynamics across a decade. The DRM approach is general and can be applied to a wide range of species with historical observations across space and time. By explicitly modeling demographic processes and their relationship to climate, DRMs promise to substantially advance prediction of species on the move.

FISHGLOB brings together experts in, and users of, fish monitoring data to support biodiversity research and conservation across oceans.

Turnover in species composition through time is a dominant form of biodiversity change, which has profound effects on the functioning of ecological communities1, 2, 3–4. Turnover rates differ markedly among communities⁴, but the drivers of this variation across taxa and realms remain unknown. Here we analyse 42,255 time series of species composition from marine, terrestrial and freshwater assemblages, and show that temporal rates of turnover were consistently faster in locations that experienced faster temperature change, including both warming and cooling. In addition, assemblages with limited access to microclimate refugia or that faced stronger human impacts on land were especially responsive to temperature change, with up to 48% of species replaced per decade. These results reveal a widespread signal of vulnerability to continuing climate change and highlight which ecological communities are most sensitive, raising concerns about ecosystem integrity as climate change and other human impacts accelerate.

Climate change is altering species’ distributions globally. Increasing frequency of extreme weather and climate events (EWCEs), including heat waves, droughts, storms, floods, and fires, is one of the hallmarks of climate change. These events can trigger rapid shifts in species’ distributions by impacting dispersal, establishment, and survival of organisms. Despite species redistribution being widely studied in response to longer-term trends of climate change, few studies consider the contribution of EWCEs to range shifts. With EWCEs impacting ecologically, economically, and culturally important species, we call for integrating EWCEs into the study of biodiversity redistribution. Advances in data availability and statistical methods are improving our capacity to understand and integrate these complex processes into adaptive conservation management efforts and biodiversity assessments.

Water temperature is a strong driver of growth, survival, and local adaptation in corals, but our knowledge of the temperatures experienced by corals on reefs worldwide remains limited. While in situ temperature loggers can provide high quality data, they are relatively expensive to place and retrieve. Alternatively, remotely sensed sea surface temperature data are globally available but may be a biased representation of the temperatures experienced by corals. Here, we compared data from 314 temperature loggers on coral reefs to the ~ 1 km² resolution remotely sensed Multi-scale Ultra-high Resolution Sea Surface Temperature (MUR) product from NASA. We found good agreement (Pearson’s r = 0.95) between maximum monthly mean temperatures calculated from remote and in situ data, with 84% of temperatures within 0.5 °C of each other. However, remotely sensed temperature did not effectively capture sub-diel temperature fluctuations and the highest peak temperatures that may be most dangerous for corals. Predictions of in situ temperatures were significantly but weakly improved by a consideration of reef geomorphology. Ultimately, we found that remotely sensed temperatures can accurately represent the monthly conditions experienced by most corals but should be used with caution at finer temporal scales.

Humans have transformed ecosystems through habitat modification, harvesting, species introduction, and climate change. Changes in species distribution and composition are often thought to induce biotic homogenization, defined as a decline in spatial beta diversity through time. However, it is unclear whether homogenization is common in ocean ecosystems and if changes in beta diversity exhibit linear or more complex dynamics. Here, we assessed patterns of homogenization or its converse (differentiation) across more than 175,000 samples of 2,006 demersal fish species from 34 regions spanning six decades and 20% of the planet’s continental shelf area. While ten regions (29%) recorded significant homogenization, eleven (32%) recorded significant differentiation. Non-monotonic temporal fluctuations in beta diversity occurred in 15 regions, highlighting complex dynamics missed by before-and-after snapshots that can drive spurious conclusions about trends in beta diversity. Fishing pressure and temperature helped explain variance in beta diversity across years and regions. However, the strength and direction of these effects differed by region. Here we showed that, despite intense anthropogenic impacts on the oceans, the majority of demersal marine fish communities do not follow the global homogenization paradigm common in other realms.