Impacts of marine heatwaves may be mediated by seabird life history strategies

Marine Ecology Progress Series, Journal Year: 2023, Volume and Issue: 737, P. 9 - 23

Published: June 1, 2023

Marine heatwaves (MHWs) are periods of anomalously warm water associated with changes in ocean structure, based on the horizontal advection masses and atmospheric exchange heat. The longest MHWs persist for many months, dramatic effects marine life have been reported from around world. As top-order predators, seabirds particularly sensitive to MHWs, high levels mortality some events, but not others. Thus, prediction impacts is straightforward, as linearly related simple measures MHW intensity, persistence, areal coverage. We describe biological responses expected seabirds, demographic parameters geographic proximity phenological timing respect seabirds. interactions between will be complex (with likely unpredictable) extend over broad spatial temporal scales. anomalous conditions breeding colonies, their overlap foraging areas, degree which coincide pre-breeding seasons presently generate greatest pressures seabird populations. posit that area-restricted species, terms movement strategies, at greater risk non-linear complicate prediction. may mediated by history strategies.

Language: Английский

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A collaborative and near-comprehensive North Pacific humpback whale photo-ID dataset

Scientific Reports, Journal Year: 2023, Volume and Issue: 13(1)

Published: June 23, 2023

We present an ocean-basin-scale dataset that includes tail fluke photographic identification (photo-ID) and encounter data for most living individual humpback whales (Megaptera novaeangliae) in the North Pacific Ocean. The was built through a broad collaboration combining 39 separate curated photo-ID catalogs, supplemented with community science data. Data from throughout were aggregated into 13 regions, including six breeding feeding one migratory corridor. All images compared minimal pre-processing using recently developed image recognition algorithm based on machine learning artificial intelligence; this system is capable of rapidly detecting matches between individuals estimated 97-99% accuracy. For 2001-2021 study period, total 27,956 unique documented 157,350 encounters. Each encountered, average, 5.6 sampling periods (i.e., seasons), annual average 87% encountered more than season. combined tool represents accessible resource collaborative, basin-wide studies keystone marine mammal time rapid ecological change.

Language: Английский

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A marine heatwave changes the stabilizing effects of biodiversity in kelp forests

Ecology, Journal Year: 2024, Volume and Issue: 105(5)

Published: March 24, 2024

Abstract Biodiversity can stabilize ecological communities through biological insurance, but climate and other environmental changes may disrupt this process via simultaneous ecosystem destabilization biodiversity loss. While to diversity–stability relationships (DSRs) the underlying mechanisms have been extensively explored in terrestrial plant communities, topic remains largely unexplored benthic marine ecosystems that comprise diverse assemblages of producers consumers. By analyzing two decades kelp forest survey data, we discovered diversity, stability, their at multiple scales (biological organizational levels, spatial scales, functional groups) were linked with most severe heatwave ever documented North Pacific Ocean. Moreover, strength DSRs during/after more apparent among groups than both levels (population vs. levels) (local broad scales). Specifically, decreased for fishes, increased mobile invertebrates understory algae, unchanged sessile heatwave. Our findings suggest plays a key role stabilizing ecosystems, resilience adverse impacts primarily depends on identities communities.

Language: Английский

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Marine habitat use and movement in response to ocean warming by a threatened forest-nesting seabird

Global Ecology and Conservation, Journal Year: 2024, Volume and Issue: 50, P. e02857 - e02857

Published: Feb. 16, 2024

Although anthropogenic climate change has resulted in significant alterations of ocean environments, the degree to which marine organisms can respond behaviorally effects remains poorly understood, especially for species with increased extinction risk. We monitored space use and movement threatened marbled murrelet (Brachyramphus marmoratus) along central coast Oregon, USA during 2017–2019 breeding seasons quantify habitat selection patterns across a range conditions. hypothesized that locations characterized by upwelling, nearshore areas adjacent old-growth forest nesting habitat, protected would be preferentially selected tagged birds. Using >4800 collected from >180 individuals, we found murrelets near small estuaries localized upwelling (as decreased sea-surface temperatures high salinity), both are expected lead greater food availability periods when elevated coastal is reduced (i.e., poor conditions). In addition, individuals did not select potential exhibited limited overlap regardless Unexpectedly, majority (62%) moved beyond boundaries our study area year poorest conditions (2017), 15% birds moving >500 km their capture location. Our results confirm becomes decoupled terrestrial conditions, such associated low propensity long-distance movements season. addition demonstrating undertake fine- coarse-scale buffer them against also emphasizes importance considering broad spatial scales environment undertaking measures conserve populations.

Language: Английский

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Variation in energy density of northwest Atlantic forage species: Ontogenetic, seasonal, annual, and spatial patterns

Marine and Coastal Fisheries, Journal Year: 2024, Volume and Issue: 16(2)

Published: April 1, 2024

Abstract Objective Energy density (ED) estimates for marine forage species have been limited, impeding our understanding of this important trophic level. We studied the EDs eight key species: Alewife Alosa pseudoharengus , Atlantic Herring Clupea harengus Silver Hake Merluccius bilinearis Northern Sand Lance Ammodytes dubius Mackerel Scomber scombrus Butterfish Peprilus triacanthus northern shortfin squid Illex illecebrosus and longfin inshore Doryteuthis pealeii (also known as Loligo ). Methods Samples were obtained during spring fall bottom trawl surveys across five regions (Gulf Maine, Georges Bank, southern New England, Middle Bight, Bight) from 2017 to 2019. In laboratory, we developed predictive relations between percent dry weight (%DW) ED (kJ/g wet weight) determined by proximate composition analysis ( n = 606; r 2 0.76–0.98) estimate additional samples 4583). For each species, modeled a function size, depth, season, year (as factors) well location (latitude, longitude) using generalized additive models (GAMs). Result Alewife, Herring, Lance, Mackerel, classified high‐quality prey (ED > 6 kJ/g), although was nearly half values reported in earlier studies. Hake, squid, moderate‐quality (4 kJ/g < kJ/g). Most had higher following summer feeding than after spawning and/or reduced winter feeding. The best‐fitting GAMs included weight, depth (by season), effects most species. Location season) explained significant amounts variation. Conclusion Observed variation regions, seasons, years provides empirical data necessary consider hypotheses related “upstream” regulation (via environmental drivers productivity) “downstream” on recruitment these that them.

Language: Английский

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