The important role of sponges in carbon and nitrogen cycling in a deep‐sea biological hotspot

Hanz, Ulrike; Riekenberg, Philip M.; Kluijver, A. de; Meer, Marcel T. J. van der; Middelburg, Jack J.; Goeij, Jasper M. de; Bart, Martijn C.; Wurz, Erik; Colaço, Ana; Duineveld, G.C.A.; Reichart, Gert‐Jan; Rapp, Hans‐Tore; Mienis, Furu

doi:10.1111/1365-2435.14117

Cited by 26 publications

(20 citation statements)

References 84 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…At the Langseth Ridge, decaying Tetractinellida sponges are covered by microbial mats and attract predators/ spongivores, such as starfishes. The starfish predates on the sponge as observed at the Schulz Bank seamount 99 and/or grazes upon the microbial mat (δ 13 C value: − 17.9‰) covering the decaying sponge (δ 13 C value: − 20.2‰) as indicated by sponge-specific fatty acids and the higher δ 13 C value of − 13.4‰ 50 . We hypothesize that feces produced by the starfish are subsequently recycled by the cryptic community living hidden in the sponge spicule-polychaete tube mats, such as amphipods, tanaidaceans, gastropods, and polychaetes 83 .…”

Section: Discussionmentioning

confidence: 99%

Habitat types and megabenthos composition from three sponge-dominated high-Arctic seamounts

Stratmann

Simon-Lledó

Morganti

et al. 2022

Sci Rep

Self Cite

View full text Add to dashboard Cite

Seamounts are isolated underwater mountains stretching > 1000 m above the seafloor. They are identified as biodiversity hotspots of marine life, and host benthic assemblages that may vary on regional (among seamounts) and local (within seamounts) scales. Here, we collected seafloor imagery of three seamounts at the Langseth Ridge in the central Arctic Ocean to assess habitats and megabenthos community composition at the Central Mount (CM), the Karasik Seamount (KS), and the Northern Mount (NM). The majority of seafloor across these seamounts comprised bare rock, covered with a mixed layer of sponge spicule mats intermixed with detrital debris composed of polychaete tubes, and sand, gravel, and/or rocks. The megabenthos assemblages consisted of in total 15 invertebrate epibenthos taxa and 4 fish taxa, contributing to mean megabenthos densities of 55,745 ind. ha−1 at CM, 110,442 ind. ha−1 at KS, and 65,849 ind. ha−1 at NM. The faunal assemblages at all three seamounts were dominated by habitat-forming Tetractinellida sponges that contributed between 66% (KS) and 85% (CM) to all megabenthos. Interestingly, taxa richness did not differ at regional and local scale, whereas the megabenthos community composition did. Abiotic and biogenic factors shaping distinct habitat types played a major role in structuring of benthic communities in high-Arctic seamounts.

show abstract

Section: Discussionmentioning

confidence: 99%

Habitat types and megabenthos composition from three sponge-dominated high-Arctic seamounts

Stratmann

Simon-Lledó

Morganti

et al. 2022

Sci Rep

Self Cite

View full text Add to dashboard Cite

show abstract

“…via the consumption of microbes via phagocytosis (Leys et al ., 2018). Mediating diverse internal and external recycling pathways, sponges act on and connect several trophic levels and play an ubiquitous role in deep‐sea ecosystems (Hanz et al ., 2022). CWCs also host a microbiome, enabling them to perform similar nutrient fluxes, but these play a minor quantitative role in the total CWC metabolism (Middelburg et al ., 2015).…”

Section: How Do Cold‐water Coral Reefs Sustain Their High Food Demand?mentioning

confidence: 99%

On the paradox of thriving cold‐water coral reefs in the food‐limited deep sea

et al. 2023

View full text Add to dashboard Cite

The deep sea is amongst the most food‐limited habitats on Earth, as only a small fraction (<4%) of the surface primary production is exported below 200 m water depth. Here, cold‐water coral (CWC) reefs form oases of life: their biodiversity compares with tropical coral reefs, their biomass and metabolic activity exceed other deep‐sea ecosystems by far. We critically assess the paradox of thriving CWC reefs in the food‐limited deep sea, by reviewing the literature and open‐access data on CWC habitats. This review shows firstly that CWCs typically occur in areas where the food supply is not constantly low, but undergoes pronounced temporal variation. High currents, downwelling and/or vertically migrating zooplankton temporally boost the export of surface organic matter to the seabed, creating ‘feast’ conditions, interspersed with ‘famine’ periods during the non‐productive season. Secondly, CWCs, particularly the most common reef‐builder Desmophyllum pertusum (formerly known as Lophelia pertusa), are well adapted to these fluctuations in food availability. Laboratory and in situ measurements revealed their dietary flexibility, tissue reserves, and temporal variation in growth and energy allocation. Thirdly, the high structural and functional diversity of CWC reefs increases resource retention: acting as giant filters and sustaining complex food webs with diverse recycling pathways, the reefs optimise resource gains over losses. Anthropogenic pressures, including climate change and ocean acidification, threaten this fragile equilibrium through decreased resource supply, increased energy costs, and dissolution of the calcium‐carbonate reef framework. Based on this review, we suggest additional criteria to judge the health of CWC reefs and their chance to persist in the future.

show abstract

“…Mean TP CSIA estimates for Florida (1.7-2.6) were surprisingly low for a secondary consumer. In a recent application of CSIA-AA to a deep-sea food web, Hanz et al (2022) observed TP CSIA estimates of 2-2.5 for LMA sponges and 1.3 for HMA sponges, akin to a primary producer (TP = 1). These results, combined with those herein, demonstrate that it may be uniquely challenging to estimate TP CSIA for sponge predators and calculate exact TP CSIA differences between hawksbills in Florida and Texas because the isotope dynamics of sponges are not well understood.…”

Section: Regionally Variable Hawksbill Dietsmentioning

confidence: 99%

Dietary plasticity linked to divergent growth trajectories in a critically endangered sea turtle

Ramirez

Avens²,

Meylan³

et al. 2023

Front. Ecol. Evol.

View full text Add to dashboard Cite

Foraging habitat selection and diet quality are key factors that influence individual fitness and meta-population dynamics through effects on demographic rates. There is growing evidence that sea turtles exhibit regional differences in somatic growth linked to alternative dispersal patterns during the oceanic life stage. Yet, the role of habitat quality and diet in shaping somatic growth rates is poorly understood. Here, we evaluate whether diet variation is linked to regional growth variation in hawksbill sea turtles (Eretmochelys imbricata), which grow significantly slower in Texas, United States versus Florida, United States, through novel integrations of skeletal growth, gastrointestinal content (GI), and bulk tissue and amino acid (AA)-specific stable nitrogen (δ15N) and carbon (δ13C) isotope analyses. We also used AA δ15N ΣV values (heterotrophic bacterial re-synthesis index) and δ13C essential AA (δ13CEAA) fingerprinting to test assumptions about the energy sources fueling hawksbill food webs regionally. GI content analyses, framed within a global synthesis of hawksbill dietary plasticity, revealed that relatively fast-growing hawksbills stranded in Florida conformed with assumptions of extensive spongivory for this species. In contrast, relatively slow-growing hawksbills stranded in Texas consumed considerable amounts of non-sponge invertebrate prey and appear to forage higher in the food web as indicated by isotopic niche metrics and higher AA δ15N-based trophic position estimates internally indexed to baseline nitrogen isotope variation. However, regional differences in estimated trophic position may also be driven by unique isotope dynamics of sponge food webs. AA δ15N ΣV values and δ13CEAA fingerprinting indicated minimal bacterial re-synthesis of organic matter (ΣV < 2) and that eukaryotic microalgae were the primary energy source supporting hawksbill food webs. These findings run contrary to assumptions that hawksbill diets predominantly comprise high microbial abundance sponges expected to primarily derive energy from bacterial symbionts. Our findings suggest alternative foraging patterns could underlie regional variation in hawksbill growth rates, as divergence from typical sponge prey might correspond with increased energy expenditure and reduced foraging success or diet quality. As a result, differential dispersal patterns may infer substantial individual and population fitness costs and represent a previously unrecognized challenge to the persistence and recovery of this critically endangered species.

show abstract

The important role of sponges in carbon and nitrogen cycling in a deep‐sea biological hotspot

Cited by 26 publications

References 84 publications

Habitat types and megabenthos composition from three sponge-dominated high-Arctic seamounts

Habitat types and megabenthos composition from three sponge-dominated high-Arctic seamounts

On the paradox of thriving cold‐water coral reefs in the food‐limited deep sea

Dietary plasticity linked to divergent growth trajectories in a critically endangered sea turtle

Contact Info

Product

Resources

About