North to south: ecosystem features determine seagrass community response to sea otter foraging

We compared sea otter recovery in California (CA) and British Columbia (BC) to determine how key ecosystem properties shape top-down effects in seagrass communities. Potential ecosystem drivers of sea otter foraging in CA and BC seagrass beds that we examined include the role of coastline complexity and environmental stress on sea otter effects. In BC, we found greater species richness across seagrass trophic assemblages. Furthermore, Cancer spp. crabs, an important link in the seagrass trophic cascade observed in CA, was less common. Additionally, the more recent reintroduction of sea otters, more complex coastline, and reduced environmental stress in BC seagrass habitats supported the hypothesis that sea otter foraging pressure is currently reduced in more northern latitudes. In order to manage the ecosystem features that lead to regional differences in top predator effects in seagrass communities, we review our findings, their spatial and temporal constraints, and present a social-ecological framework for future re- search

Deeper habitats and cooler temperatures moderate a climate-driven seagrass disease

Eelgrass creates critical coastal habitats worldwide and fulfills essential ecosystem functions as a foundation seagrass. Climate warming and disease threaten eelgrass, causing mass mortalities and cascading ecological impacts. Subtidal meadows are deeper than intertidal and may also provide refuge from the temperature-sensitive seagrass wasting disease. From cross-boundary surveys of 5761 eelgrass leaves from Alaska to Washington and assisted with a machine-language algorithm, we measured outbreak conditions. Across summers 2017 and 2018, disease prevalence was 16% lower for subtidal than intertidal leaves; in both tidal zones, disease risk was lower for plants in cooler conditions. Even in subtidal meadows, which are more environmentally stable and sheltered from temperature and other stressors common for intertidal eelgrass, we observed high disease levels, with half of the sites exceeding 50% prevalence. Models predicted reduced disease prevalence and severity under cooler conditions, confirming a strong interaction between disease and temperature. At both tidal zones, prevalence was lower in more dense eelgrass meadows, suggesting disease is suppressed in healthy, higher density meadows. These results underscore the value of subtidal eelgrass and meadows in cooler locations as refugia, indicate that cooling can suppress disease, and have implications for eelgrass conservation and management under future climate change scenarios

Disease surveillance by artificial intelligence links eelgrass wasting disease to ocean warming across latitudes

Ocean warming endangers coastal ecosystems through increased risk of infectious disease, yet detection, surveillance, and forecasting of marine diseases remain limited. Eelgrass (Zostera marina) meadows provide essential coastal habitat and are vulnerable to a temperature-sensitive wasting disease caused by the protist Labyrinthula zosterae. We assessed wasting disease sensitivity to warming temperatures across a 3500 km study range by combining long-term satellite remote sensing of ocean temperature with field surveys from 32 meadows along the Pacific coast of North America in 2019. Between 11% and 99% of plants were infected in individual meadows, with up to 35% of plant tissue damaged. Disease prevalence was 3× higher in locations with warm temperature anomalies in summer, indicating that the risk of wasting disease will increase with climate warming throughout the geographic range for eelgrass. Large-scale surveys were made possible for the first time by the Eelgrass Lesion Image Segmentation Application, an artificial intelligence (AI) system that quantifies eelgrass wasting disease 5000× faster and with comparable accuracy to a human expert. This study highlights the value of AI in marine biological observing specifically for detecting widespread climate-driven disease outbreaks.This work was supported by the National Science Foundation (awards OCE-1829921, OCE-1829922, OCE-1829992, OCE-1829890). This is contribution 104 from the Smithsonian's MarineGEO and Tennenbaum Marine Observatories Network.Peer reviewe

Climate drives the geography of marine consumption by changing predator communities

Este artículo contiene 7 páginas, 3 figuras, 1 tabla.The global distribution of primary production and consumption by humans (fisheries) is well-documented, but we have no map linking the central ecological process of consumption within food webs to temperature and other ecological drivers. Using standardized assays that span 105° of latitude on four continents, we show that rates of bait consumption by generalist predators in shallow marine ecosystems are tightly linked to both temperature and the composition of consumer assemblages. Unexpectedly, rates of consumption peaked at midlatitudes (25 to 35°) in both Northern and Southern Hemispheres across both seagrass and unvegetated sediment habitats. This pattern contrasts with terrestrial systems, where biotic interactions reportedly weaken away from the equator, but it parallels an emerging pattern of a subtropical peak in marine biodiversity. The higher consumption at midlatitudes was closely related to the type of consumers present, which explained rates of consumption better than consumer density, biomass, species diversity, or habitat. Indeed, the apparent effect of temperature on consumption was mostly driven by temperature-associated turnover in consumer community composition. Our findings reinforce the key influence of climate warming on altered species composition and highlight its implications for the functioning of Earth’s ecosystems.We acknowledge funding from the Smithsonian Institution and the Tula Foundation.Peer reviewe

Global challenges for seagrass conservation

Seagrasses, flowering marine plants that form underwater meadows, play a significant global role in supporting food security, mitigating climate change and supporting biodiversity. Although progress is being made to conserve seagrass meadows in select areas, most meadows remain under significant pressure resulting in a decline in meadow condition and loss of function. Effective management strategies need to be implemented to reverse seagrass loss and enhance their fundamental role in coastal ocean habitats. Here we propose that seagrass meadows globally face a series of significant common challenges that must be addressed from a multifaceted and interdisciplinary perspective in order to achieve global conservation of seagrass meadows. The six main global challenges to seagrass conservation are (1) a lack of awareness of what seagrasses are and a limited societal recognition of the importance of seagrasses in coastal systems; (2) the status of many seagrass meadows are unknown, and up-to-date information on status and condition is essential; (3) understanding threatening activities at local scales is required to target management actions accordingly; (4) expanding our understanding of interactions between the socio-economic and ecological elements of seagrass systems is essential to balance the needs of people and the planet; (5) seagrass research should be expanded to generate scientific inquiries that support conservation actions; (6) increased understanding of the linkages between seagrass and climate change is required to adapt conservation accordingly. We also explicitly outline a series of proposed policy actions that will enable the scientific and conservation community to rise to these challenges. We urge the seagrass conservation community to engage stakeholders from local resource users to international policy-makers to address the challenges outlined here, in order to secure the future of the world’s seagrass ecosystems and maintain the vital services which they supply

Effects of Anacetrapib in Patients with Atherosclerotic Vascular Disease

BACKGROUND: Patients with atherosclerotic vascular disease remain at high risk for cardiovascular events despite effective statin-based treatment of low-density lipoprotein (LDL) cholesterol levels. The inhibition of cholesteryl ester transfer protein (CETP) by anacetrapib reduces LDL cholesterol levels and increases high-density lipoprotein (HDL) cholesterol levels. However, trials of other CETP inhibitors have shown neutral or adverse effects on cardiovascular outcomes. METHODS: We conducted a randomized, double-blind, placebo-controlled trial involving 30,449 adults with atherosclerotic vascular disease who were receiving intensive atorvastatin therapy and who had a mean LDL cholesterol level of 61 mg per deciliter (1.58 mmol per liter), a mean non-HDL cholesterol level of 92 mg per deciliter (2.38 mmol per liter), and a mean HDL cholesterol level of 40 mg per deciliter (1.03 mmol per liter). The patients were assigned to receive either 100 mg of anacetrapib once daily (15,225 patients) or matching placebo (15,224 patients). The primary outcome was the first major coronary event, a composite of coronary death, myocardial infarction, or coronary revascularization. RESULTS: During the median follow-up period of 4.1 years, the primary outcome occurred in significantly fewer patients in the anacetrapib group than in the placebo group (1640 of 15,225 patients [10.8%] vs. 1803 of 15,224 patients [11.8%]; rate ratio, 0.91; 95% confidence interval, 0.85 to 0.97; P=0.004). The relative difference in risk was similar across multiple prespecified subgroups. At the trial midpoint, the mean level of HDL cholesterol was higher by 43 mg per deciliter (1.12 mmol per liter) in the anacetrapib group than in the placebo group (a relative difference of 104%), and the mean level of non-HDL cholesterol was lower by 17 mg per deciliter (0.44 mmol per liter), a relative difference of -18%. There were no significant between-group differences in the risk of death, cancer, or other serious adverse events. CONCLUSIONS: Among patients with atherosclerotic vascular disease who were receiving intensive statin therapy, the use of anacetrapib resulted in a lower incidence of major coronary events than the use of placebo. (Funded by Merck and others; Current Controlled Trials number, ISRCTN48678192 ; ClinicalTrials.gov number, NCT01252953 ; and EudraCT number, 2010-023467-18 .)

Monitoring the growth and survival of larval herring on B.C. central coast

Herring spawning on British Columbia’s central coast takes place in the early spring. Strength of a year class is largely dependent on successful recruitment from the larval stage to the adult population. The potential temporal and spatial overlap of herring larval distribution with spring bloom dynamics can be a major determining factor in the success of larvae in finding suitable prey, with delayed feeding potentially leading to mass mortality. Consequently the phenology and productivity of plankton blooms, as well as the interannual variability in spawning at active sites can be significant. Reporting on data since 2012, we observe that although spawn timing does vary from year to year, this variation is less than that associated with spring bloom timing. The prey conditions experienced by larvae are therefore expected to vary significantly from one year, and site, to the next. In fact, larval growth at 38% of sites sampled wa

The value of ecosystem services in global marine kelp forests

While marine kelp forests have provided valuable ecosystem services for millennia, the global ecological and economic value of those services is largely unresolved. Kelp forests are diminishing in many regions worldwide, and efforts to manage these ecosystems are hindered without accurate estimates of the value of the services that kelp forests provide to human societies. Here, we present a global estimate of the ecological and economic potential of three key ecosystem services - fisheries production, nutrient cycling, and carbon removal provided by six major forest forming kelp genera (Ecklonia, Laminaria, Lessonia, Macrocystis, Nereocystis, and Saccharina). Each of these genera creates a potential value of between $64,400 and$147,100/hectare each year. Collectively, they generate between $465 and$562 billion/year worldwide, with an average of $500 billion. These values are primarily driven by fisheries production (mean$29,900, 904 Kg/Ha/year) and nitrogen removal ($73,800, 657 Kg N/Ha/year), though kelp forests are also estimated to sequester 4.91 megatons of carbon from the atmosphere/year highlighting their potential as blue carbon systems for climate change mitigation. These findings highlight the ecological and economic value of kelp forests to society and will facilitate better informed marine management and conservation decisions

Data and code from: Deeper habitats and cooler temperatures moderate a climate-driven disease in an essential marine habitat

Please cite as: Olivia Graham, Tiffany Stephens, Brendan Rappazzo, Corinne Klohmann, Sukanya Dayal, Emily Adamczyk, Angeleen Olson, Margot Hessing-Lewis, Morgan Eisenlord, Bo Yang, Colleen Burge, Carla Gomes, Drew Harvell. (2022) Data and code from: Deeper habitats and cooler temperatures moderate a climate-driven disease in an essential marine habitat [dataset] Cornell University eCommons Repository. https://doi.org/10.7298/6ybh-w566These files contain data and R code supporting all results reported in Graham et al. "Deeper habitats and cooler temperatures moderate a climate-driven disease in an essential marine habitat." In Graham et al., we found: Eelgrass creates critical coastal habitats worldwide and fulfills essential ecosystem functions as a foundation seagrass. Warming and disease threaten eelgrass meadows with mass mortalities and cascading ecological impacts, even in pristine locations. Although deeper, subtidal meadows are valuable fish nursery grounds and may also provide refuge from the climate-fueled seagrass wasting disease, nothing is known about differences in disease levels across remote locations in northern latitudes and between tidal zones (intertidal and subtidal meadows). From cross-boundary surveys on 5,761 eelgrass leaves from Alaska to Washington assisted with a machine-language algorithm, we measured outbreak conditions with average disease prevalence over 66% in intertidal and 50% in subtidal. In field surveys, disease was consistently lower in subtidal compared to adjacent intertidal meadows; remotely-sensed temperatures revealed significant associations between spring temperature anomalies and disease. While new studies show links between warm temperature anomalies and increased disease, our work detects beneficial effects of cooling in colder water anomalies. Disease was reduced in all regions except Puget Sound in the cooler summer of 2017. Pooled across both years, predicted disease prevalence was nearly 40% lower for subtidal than intertidal leaves, but in both tidal zones, disease risk was lower for plants in cooler conditions. Even in the ecologically most valuable subtidal meadows, we observed high disease levels, with half of the sites exceeding 50% prevalence. Disease models predicted reduced disease prevalence and severity under cooler conditions, confirming a strong interaction between disease and temperature. Finally, at both tidal zones, prevalence was reduced in more dense eelgrass meadows, suggesting disease is suppressed in healthy, higher density meadows. These results highlight the value of subtidal eelgrass meadows and meadows in cooler locations as refugia from the highest disease levels, indicate cooling can suppress disease, and have implications for eelgrass conservation and management under future climate change scenarios.The following generous funds supported this work: Cornell University’s Atkinson Center for Sustainable Biodiversity Fund, Cornell Engaged Graduate Student Grant, Cornell Sigma Xi Research Grant, Andrew W. Mellon Student Research Grant, Dr. Carolyn Haugen, University of Washington Friday Harbor Labs Graduate Research Fellowship Endowment, Women Diver’s Hall of Fame Scholarship in Marine Conservation to OJG; NSF-REU and Susan Lynch support for the Cornell Ocean Research Apprenticeship for Lynch Scholars to CK and SD; NSF awards OCE-1829921 and Washington SeaGrant (grant #NA18OAR4170095) to CB, Carolyn Friedman, CDH; NSF CompSustNet: Expanding the Horizons of Computational Sustainability (grant #1522054) to CG; Tula Foundation to OJG, EA, AO, MHL