bioRxiv Science⌕ Search

Biology subjects

Haslob, H.

Publications and source records attributed to Haslob, H..

2 recordsLinked to original sources
bioRxiv2025

Flatfish intestinal microbiota depend on various host traits, and vary with sediment type and bottom trawling effort

The intestinal microbiota of fishes support digestion, nutrient uptake and play an important role in the immune system, development and reproduction. Flatfish live in close contact with the seafloor, and are particularly exposed to anthropogenic disturbances such as bottom trawling. Bottom trawling impacts the ecosystem in various ways and it recent evidence indicates that the microbial composition and diversity in marine sediments varies with fishing intensity. It is presently unknown whether this trawling signal applies to the seafloor alone, or may also extend to microbiota of marine holobionts inhabiting it, such as flatfishes. Here, three flatfish species (Buglossidium luteum, Limanda limanda and Pleuronectes platessa) were sampled across the southeastern North Sea. We characterized the intestinal microbiota using 16S rDNA metabarcoding of 162 individuals, and disentangled how intestinal microbial composition and diversity are jointly shaped by various host traits (species, sex, age, weight, and condition factor) and environmental factors (sediment type and trawling intensity). Intestinal diversity varied among species and changed with age, weight and sediment type. Community composition was dependent on species, age, condition factor and sediment type. In addition, we found that trawling intensity explained shifts in intestinal microbial community composition, suggesting that the known impacts of bottom trawling on the benthic environment may cascade to intestinal microbiota of flatfish. Our findings provide important insight into host-microbiota interactions in marine ecosystems and highlight the interplay between host traits and environment as drivers of intestinal microbial diversity and community composition in flatfish. HighlightsO_LIFlatfish microbiota are shaped by host traits and environmental factors C_LIO_LIHost species and age affect intestinal microbial diversity and composition C_LIO_LIIntestinal microbiota vary along a bottom trawling intensity gradient C_LIO_LIBottom trawling impacts may cascade from sediments to fish intestinal microbiota C_LI

ecology↗
bioRxiv2025

Current and future relevance of marine spatial planning for the distribution of epibenthic invertebrate and fish species in a heavily used regional sea

The SNS has recently become a European hub for installations of offshore wind farms (OWF), while extensive areas have been designated as marine protected areas (MPAs). Together with the already noticeable effects of climate warming, the region transforms from an area dominated by free ranging fisheries and shipping into an industrial landscape dominated by stationary activities. To inform decision making processes around the spatial allocation of fisheries, conservation measures and licence areas for offshore renewables in the southern North Sea, we modelled the spatial distribution of 179 epibenthic invertebrate and fish species. We identify both current and future hotspots of epibenthic and demersal fish diversity and their overlap with OWFs and MPAs. Hotspots of epibenthic and fish diversity are mostly found along the English Coast, located within an extensive network of MPA and OWF sites, which may provide opportunities for conservation and fisheries alike. In the central SNS, the MPA network could be complemented by OWF, where co-use regulations with other human uses are excluded, to protect sensitive species as well as epibenthic and demersal fish communities. Scenarios for three different time periods (until 2040, 2070 & 2100) revealed that global warming might cause an increase in the probability of occurrence for more than half of the analysed demersal fish species (n = 63). The applications in our study demonstrate the relevance of comprehensive knowledge about current, near and far future distribution patterns of species and species communities to enhance the effectiveness of marine spatial planning including spatial conservation measures.

ecology↗