Global biogeography of marine amphipod crustaceans : latitude, regionalisation, and beta diversity

Author's accepted version (postprint).This is an Accepted Manuscript of an article published by Inter-Research Science Publisher in Marine Ecology Progress Series on 19/03/2020.Available online: https://www.int-res.com/abstracts/meps/v638/p83-94/acceptedVersio

A modelled global distribution of the kelp biome

Author's accepted version (postprint).This is an Accepted Manuscript of an article published by Elsevier in Biological Conservation on 17/11/2020.Available online: https://www.sciencedirect.com/science/article/pii/S0006320720308739?via%3DihubacceptedVersio

Not all biodiversity rich spots are climate refugia

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Conserving threatened marine species and biodiversity requires 40% ocean protection

Global prioritisation of where to locate Marine Protected Areas (MPA) has not considered both a comprehensive range of measures of biodiversity as well as threatened species distributions. Using maps of 974 threatened species ranges, we found that areas of high threatened species richness are distributed throughout the world's coastal and continental shelf areas as well as in offshore regions and well-known biodiversity hotpots. We then assessed whether Representative Biodiversity Areas (RBAs), the top 30% of the global ocean prioritised based on holistic measures of biodiversity from genes to ecosystems, adequately cover the ranges of threatened species. Implementing RBAs could protect a minimum of 30% of most threatened species ranges, but 26 threatened species have distributions in areas with poor overlap with biodiversity priorities. Using decision support software we found that a minimum of 40% of the ocean is required to adequately protect over 68% of all aspects of biodiversity and 30% of IUCN Red List threatened species ranges. Priority areas outside Exclusive Economic Zones (39%) demonstrate the importance of the High Seas (59% of the global oceans) to biodiversity conservation. Recognising the uncertainties inherent in our approach due to the limited proportion of taxa assessed by the IUCN Red List, we used an uncertainty analysis to support our findings. We found that currently, only 2.5% of priority areas are within marine reserves, highlighting the urgent need for increased protection of important areas for biodiversity and threatened species across EEZs and the High Seas.publishedVersio

Body size and trophic level increase with latitude, and decrease in the deep-sea and Antarctica, for marine fish species

The functional traits of species depend both on species’ evolutionary characteristics and their local environmental conditions and opportunities. The temperature-size rule (TSR), gill-oxygen limitation theory (GOLT), and temperature constraint hypothesis (TCH) have been proposed to explain the gradients of body size and trophic level of marine species. However, how functional traits vary both with latitude and depth have not been quantified at a global scale for any marine taxon. We compared the latitudinal gradients of trophic level and maximum body size of 5,619 marine fish from modelled species ranges, based on (1) three body size ranges, 100 cm, and (2) four trophic levels, 3.70. These were parsed into 5° latitudinal intervals in four depth zones: whole water column, 0–200, 201–1,000, and 1,001–6,000 m. We described the relationship between latitudinal gradients of functional traits and salinity, sea surface and near seabed temperatures, and dissolved oxygen. We found mean body sizes and mean trophic levels of marine fish were smaller and lower in the warmer latitudes, and larger and higher respectively in the high latitudes except for the Southern Ocean (Antarctica). Fish species with trophic levels ≤2.80 were dominant in warmer and absent in colder environments. We attribute these differences in body size and trophic level between polar regions to the greater environmental heterogeneity of the Arctic compared to Antarctica. We suggest that fish species’ mean maximum body size declined with depth because of decreased dissolved oxygen. These results support the TSR, GOLT and TCH hypotheses respectively. Thus, at the global scale, temperature and oxygen are primary factors affecting marine fishes’ biogeography and biological traits

Progress in the discovery of amphipod crustaceans

At present, amphipod crustaceans comprise 9,980 species, 1,664 genera, 444 subfamilies, and 221 families. Of these, 1,940 species (almost 20%) have been discovered within the last decade, including 18 fossil records for amphipods, which mostly occurred in Miocene amber and are probably all freshwater species. There have been more authors describing species since the 1950s and fewer species described per author since the 1860s, implying greater taxonomic effort and that it might be harder to find new amphipod species, respectively. There was no evidence of any change in papers per author or publication life-times of taxonomists over time that might have biased apparent effort. Using a nonhomogeneous renewal process model, we predicted that by the year 2100, 5,600 to 6,600 new amphipod species will be discovered. This indicates that about two-thirds of amphipods remain to be discovered which is twice the proportion than for species overall. Amphipods thus rank amongst the least well described taxa. To increase the prospect of discovering new amphipod species, studying undersampled areas and benthic microhabitats are recommended

Warmer temperature decreases the maximum length of six species of marine fishes, crustacean, and squid in New Zealand

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Where marine protected areas would best represent 30% of ocean biodiversity

Author's accepted version (postprint).This is an Accepted Manuscript of an article published by Elsevier in Biological Conservation on 02/04/2020.Available online: https://www.sciencedirect.com/science/article/pii/S0006320719312182?via%3DihubThe IUCN (the International Union for Conservation of Nature) World Conservation Congress called for the full protection of 30% of each marine habitat globally andat least 30% of all the ocean. Thus, we quantitatively prioritized the top 30% areas for Marine Protected Areas (MPAs) globally using global scale measures ofbiodiversity from the species to ecosystem level. The analysis used (a) Ecosystems mapped based on 20 environmental variables, (b) four Biomes (seagrass, kelp,mangrove, and shallow water coral reefs) plus seabed rugosity as a proxy for habitat, and (c) species richness within each biogeographic Realm (indicating areas ofspecies endemicity), so as to maximise representivity of biodiversity overall.We found that the 30% prioritized areas were mainly on continental coasts, island arcs, oceanic islands, the southwest Indian Ridge, the northern Mid-AtlanticRidge, the Coral Triangle, Caribbean Sea, and Arctic Archipelago. They generally covered 30% of the Ecosystems and over 80% of the Biomes. Although 58% of theareas were within countries Exclusive EconomicZones(EEZ), only 10% were in MPAs, and < 1% in no-take MPAs (IUCN category Ia). These prioritized areas indicatewhere it would be optimal to locate MPAs for recovery of marine biodiversity within and outside country's EEZ. Our results thus provide a map that will aid bothnational and international planning of where to protect marine biodiversity as a whole.acceptedVersio

The TREC2001 video track: information retrieval on digital video information

The development of techniques to support content-based access to archives of digital video information has recently started to receive much attention from the research community. During 2001, the annual TREC activity, which has been benchmarking the performance of information retrieval techniques on a range of media for 10 years, included a ”track“ or activity which allowed investigation into approaches to support searching through a video library. This paper is not intended to provide a comprehensive picture of the different approaches taken by the TREC2001 video track participants but instead we give an overview of the TREC video search task and a thumbnail sketch of the approaches taken by different groups. The reason for writing this paper is to highlight the message from the TREC video track that there are now a variety of approaches available for searching and browsing through digital video archives, that these approaches do work, are scalable to larger archives and can yield useful retrieval performance for users. This has important implications in making digital libraries of video information attainable

Numbers of fish species, higher taxa, and phylogenetic similarity decrease with latitude and depth, and deep-sea assemblages are unique

Species richness has been found to increase from the poles to the tropics but with a small dip near the equator over all marine fishes. Phylogenetic diversity measures offer an alternative perspective on biodiversity linked to evolutionary history. If phylogenetic diversity is standardized for species richness, then it may indicate places with relatively high genetic diversity. Latitudes and depths with both high species and phylogenetic diversity would be a priority for conservation. We compared latitudinal and depth gradients of species richness, and three measures of phylogenetic diversity, namely average phylogenetic diversity (AvPD), the sum of the higher taxonomic levels (STL) and the sum of the higher taxonomic levels divided by the number of species (STL/spp) for modelled ranges of 5,619 marine fish species. We distinguished all, bony and cartilaginous fish groups and four depth zones namely: whole water column; 0 –200 m; 201–1,000 m; and 1,001–6,000 m; at 5°  latitudinal intervals from 75°S to 75°N, and at 100 m depth intervals from 0 m to 3,500 m. Species richness and higher taxonomic richness (STL) were higher in the tropics and subtropics with a small dip at the equator, and were significantly correlated among fish groups and depth zones. Species assemblages had closer phylogenetic relationships (lower AvPD and STL/spp) in warmer (low latitudes and shallow water) than colder environments (high latitudes and deep sea). This supports the hypothesis that warmer shallow latitudes and depths have had higher rates of evolution across a range of higher taxa. We also found distinct assemblages of species in different depth zones such that deeper sea species are not simply a subset of shallow assemblages. Thus, conservation needs to be representative of all latitudes and depth zones to encompass global biodiversity