Elephant seals as ecosystem sentinels for the northeast Pacific Ocean twilight zone

Science, Journal Year: 2025, Volume and Issue: 387(6735), P. 764 - 769

Published: Jan. 2, 2025

The open ocean twilight zone holds most of the global fish biomass but is poorly understood owing to difficulties measuring subsurface ecosystem processes at scale. We demonstrate that a wide-ranging carnivore—the northern elephant seal—can serve as an sentinel for zone. link basin–scale foraging success with oceanographic indices estimate abundance five decades into past, and future. discovered small variation in maternal amplified larger changes offspring body mass enormous first-year survival recruitment. Worsening conditions could shift predator population trajectories from current growth sharp declines. As integrators, predators reveal impacts future anthropogenic change on ecosystems.

Language: Английский

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A grazer's niche edge is associated with increasing diet diversity and poor population performance

Ecology Letters, Journal Year: 2024, Volume and Issue: 27(1)

Published: Jan. 1, 2024

Abstract The core‐periphery hypothesis predicts niche cores should be associated with greater survivorship, reproductive output and population performance rates than marginal habitats at edges. However, there is very little empirical evidence of whether centrality influences trends in animals. Using the Cape mountain zebra ( Equus ) as a model system, we evaluated trends, resource availability diet across gradient. Population growth density progressively declined towards peripheries. Niche peripheries were resource‐poor consumed more phylogenetically diverse diets dominated by non‐grass families. In core they grass‐rich female success was higher. This combination spatial modelling functional ecology provides novel evaluation how bottom‐up limitation can shape species distributions, resilience range change guide conservation management.

Language: Английский

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Individual variation in life-history timing: synchronous presence, asynchronous events and phenological compensation in a wild mammal

Proceedings of the Royal Society B Biological Sciences, Journal Year: 2024, Volume and Issue: 291(2021)

Published: April 17, 2024

Many animals and plants have species-typical annual cycles, but individuals vary in their timing of life-history events. Individual variation fur replacement (moult) is poorly understood mammals due to the challenge repeated observations longitudinal sampling. We examined factors that influence moult duration among elephant seals ( Mirounga angustirostris ). quantified onset progression loss 1178 individuals. found an exceptionally rapid visible (7 days, shortest any or birds), a wide range start dates (spanning 6–10× event duration) facilitated high asynchrony across (only 20% population moulting at same time). Some was reproductive state, as reproductively mature females skipped breeding season moulted week earlier than females. Moreover, individual within age-sex categories far outweighed (76–80%) categories. Individuals arriving end spent 50% less time on beach, which allowed them catch up cycles reduce population-level variance during breeding. These findings underscore importance cycles.

Language: Английский

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Biologging for the future: how biologgers can help solve fundamental questions, from individuals to ecosystems

Published: Feb. 25, 2024

Archival instruments attached to animals (biologgers) have enabled exciting discoveries and promoted effective conservation management for decades. Recent research indicates that the field of biologging is poised shift from pattern description process explanation. Here we describe how biologgers been - can be used test hypotheses challenge theory in behavior ecology through three case studies many short examples. These examples, spanning predator-prey interactions, state-dependent risk-taking, resource tracking, collective movement decisions, show resolve long-standing mysteries if designed with a solid conceptual foundation. The next phase science will require scaling individuals populations possibly ecosystems. It also benefit building equitable international interdisciplinary partnerships, bridging terrestrial-marine divide, addressing ethical conundrums including animal handling open practices. Doing so help cement as an indispensable tool producing generalizable knowledge about organisms ecosystems function.

Language: Английский

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Reduced Body Mass in a Highly Insectivorous Mammal, the Garden Dormouse—Ecological Consequences of Insect Decline?

Ecology and Evolution, Journal Year: 2025, Volume and Issue: 15(4)

Published: April 1, 2025

Biodiversity is decreasing worldwide, and early indicators are needed to identify endangered populations before they start decline in abundance. In mammals, body mass (BM) regarded as an indicator of fitness, its loss used warning signal preceding population decline. The garden dormouse (Eliomys quercinus, Gliridae, BM: 60-110 g) a small mammalian hibernator that has disappeared from over 50% former range the last decades. aim this study was investigate whether dormice presumably thriving stable already show signals, which may precede We therefore conducted capture-mark-recapture studies during 2003-2005 (Period 1) 2018-2021 2) Northern Black Forest, one natural distribution areas Germany. collected fecal samples, measured BM, tibia length proxy for size age. Results revealed Period 2 adult had significantly lower (12%) pre-hibernation corrected size, juveniles showed BM gain after weaning than nearly two decades ago. Fecal samples arthropods represented main food residues juvenile growth fattening. Ambient temperature hibernation no correlation with at emergence. could not detect phenological time shift reproduction; however, we found only birth peak 2, compared peaks 1. Observed changes reproduction pattern represent point insufficient availability high-quality food, prevents meeting their nutritional requirements, potentially serious consequences reproductive success survival. As dominant resource, least partly explain phenomenon.

Language: Английский

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Tracking individual animals can reveal the mechanisms of species loss

Trends in Ecology & Evolution, Journal Year: 2024, Volume and Issue: unknown

Published: Nov. 1, 2024

Language: Английский

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Overcoming the pitfalls of categorizing continuous variables in ecology, evolution and behaviour

Proceedings of the Royal Society B Biological Sciences, Journal Year: 2024, Volume and Issue: 291(2032)

Published: Oct. 1, 2024

Many variables in biological research—from body size to life-history timing environmental characteristics—are measured continuously (e.g. mass kilograms) but analysed as categories large versus small), which can lower statistical power and change interpretation. We conducted a mini-review of 72 recent publications six popular ecology, evolution behaviour journals quantify the prevalence categorization. then summarized commonly categorized metrics simulated dataset demonstrate drawbacks categorization using common realistic examples. show that categorizing continuous is (31% reviewed). also underscore predictor should be collected continuously. Finally, we provide recommendations on how keep throughout entire scientific process. Together, these pieces comprise an actionable guide increasing facilitating synthesis studies by simply leaving alone. Overcoming pitfalls will allow ecologists, ethologists evolutionary biologists continue making trustworthy conclusions about natural processes, along with predictions their responses climate other contexts.

Language: Английский

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Inherent versus random variation in fitness of elephant seals: offspring quality and quantity

Canadian Journal of Zoology, Journal Year: 2024, Volume and Issue: 102(9), P. 759 - 770

Published: Sept. 1, 2024

Variation in reproductive success is the basis of evolution and allows species to respond environment, but only when it based on fixed individual variation that heritable. Several recent studies suggest observed reproduction due chance, not inherent differences. Our aim was quantify versus neutral fitness northern elephant seal ( Mirounga angustirostris (Gill, 1866)) females, including both quality quantity their offspring. Using 44 years observations at Año Nuevo California, we assembled lifetime pup production 1065 females mass weaning for 2120 pups. Females varied significantly mean pups, with 28% variance differences among mothers. repeatable over 6 a mother’s heritable h = 0.48). Moreover, associated future fitness, since larger pups had higher chance surviving breed. Larger however, did produce more offspring once breeding, Traits related seals were inherently different neutral.

Language: Английский

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Balancing Act: an Interdisciplinary Exploration of Trade-offs in Reproducing Females

Integrative and Comparative Biology, Journal Year: 2024, Volume and Issue: unknown

Published: July 8, 2024

Trade-offs resulting from the high demand of offspring production are a central focus many subdisciplines within field biology. Yet, despite historical and current interest on this topic, large gaps in our understanding whole-organism trade-offs that occur reproducing individuals remain, particularly as it relates to nuances associated with female reproduction. This volume Integrative Comparative Biology (ICB) contains series papers reviewing female-centered perspective biology (i.e., places reproductive at center topic being investigated or discussed). These represent some work showcased during symposium held 2024 meeting Society for (SICB) Seattle, Washington. In roundtable discussion, we use question-and-answer format capture diverse perspectives voices involved symposium. We hope dialogue featured discussion will be used motivate researchers interested females provide guidance future research endeavors.

Language: Английский

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Maximizing biological insights from instruments attached to animals

Trends in Ecology & Evolution, Journal Year: 2024, Volume and Issue: unknown

Published: Oct. 1, 2024

Instruments attached to animals ('biologgers') have facilitated extensive discoveries about the patterns, causes, and consequences of animal behavior. Here, we present examples how biologging can deepen our fundamental understanding ecosystems applied global change impacts by enabling tests ecological theory. Applying iterative process science has enabled a diverse set insights, including social experiential learning in long-distance migrants, state-dependent risk aversion foraging predators, resource abundance driving movement across taxa. Now, is poised tackle questions refine theories at increasing levels complexity integrating measurements from numerous individuals, merging datasets multiple species their environments, spanning disciplines, physiology, behavior demography.

Language: Английский

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