Opportunistic life histories and genetic systems in marine benthic polychaetes

The decline in benthic marine fauna following an oil spill in West Falmouth, Massachusetts, permitted us to follow the responses of a number of polychaete and other invertebrate species to an environmental disturbance. Species with the most opportunistic life histories increased and declined at the two stations with the greatest reduction in species diversity. The stations with an intermediate reduction in diversity showed increases and declines of somewhat less opportunistic species...

The Politicization and Polarization of Climate Change

In the mid to late 20th-century, climate change and other environmental issues were addressed on a bipartisan basis, with Republican politicians like President Richard Nixon and George H.W. Bush supporting and advancing measures to combat climate change. However, since the 1990s, climate change has become increasingly polarized, with significant polarization in the last decade. This paper dives into the causes behind climate change\u27s politicization and polarization and what the future holds for bipartisan agreement by analyzing peer-reviewed articles, campaign contributions, news stories, political archives, and past interviews with climate experts. The analysis finds that the polarization has been driven by numerous factors, including oil and gas industries funding of climate change denialism, the political realignment of voter geography, the tea party movement, and Trump\u27s war on science. Political polarization on climate change has peaked in 2021; however, there are promising signs for future bipartisan agreement to combat climate change. The financial sector is becoming much more environmentally conscious in their investments, including those towards the energy industry, leading to a more responsive and responsible oil & gas industry. The young GOP is also significantly more receptive to climate change measures, pushing the party to adopt free-market solutions to combat climate change

Invertebrate larval availability during summer upwelling and downwelling on the inner continental shelf off New Jersey

This study examined the effects of wind-driven, cross-shelf circulation on invertebrate larval supply to benthic habitats on the inner continental shelf off Tuckerton, New Jersey, USA. Study sites were located along an inshore/offshore transect in the LEO-15 research area at Beach Haven Ridge, a 12–20 m deep, shore-oblique sand ridge. Meroplankton was sampled using Moored, Automated, Serial Zooplankton Pumps which were programmed to take 250-l samples, ~1 m above the bottom, every 4 h. Upwelling and downwelling conditions were characterized using wind data from the nearby meteorological tower at the Rutgers University Marine Field Station, and bottom temperatures from LEO-15 node data and the pump sites. Studies were carried out during July in 1996 –1998 because previous recruitment studies showed that July was when larval surfclams, Spisula solidissima, were abundant and their settlement maximal. The study was repeated over three years to sample multiple upwelling/downwelling sequences. Although the study focused primarily on the dominant S. solidissima larvae, other meroplankton were also enumerated. Short-lived pulses (12 h or less) of highest larval surfclam concentrations (up to 3000 sample -1, sample volume = 250 l) often coincided with the initial arrival of warm water at the bottom at the initiation of downwelling, indicating a patchy larval distribution that is probably related to high larval concentrations near fronts. On one date in July 1998, very high concentrations of surfclam and pholad bivalve larvae coincided with the arrival of warm, relatively low salinity water. This pattern suggested a larval concentrating mechanism near an estuarine front, perhaps from the Hudson River plume. Sampling during multiple upwelling/downwelling events over the three summers revealed a close correlation between peaks in larval concentration of bivalves and gastropods coinciding with the arrival of downwelled warm water at the bottom at inner shelf sites

The role of colonization in establishing patterns of community composition and diversity in shallow-water sedimentary communities

To determine whether pattern and diversity in benthic sedimentary communities are set primarily at colonization or by post-settlement biological interactions, we collected faunal cores and conducted reciprocal sediment transplant experiments at a sandy and a muddy site at 12 m depth, ~3 km apart off New Jersey. Multivariate analyses of cores collected at these sites in September 1994 indicated differences in the taxa determining local pattern, with the bivalve Spisula solidissima and the polychaete Polygordius sp. being dominant at the sandy site, and oligochaetes, several polychaete species and the bivalve Nucula annulata dominant at the muddy site. Individual cores from the sandy site were significantly less diverse than those at the muddy site. Short-term experiments (3-5 d) were deployed by divers at three different times (August-September, 1994). Replicate trays (100 cm2) filled with azoic sand or mud were placed flush with the ambient seafloor at both sites. Multivariate comparisons indicated that sediment treatment in trays played a greater role in determining colonization patterns in the first experiment, site played a greater role in the second, and both variables contributed in the third. This pattern suggests that larval settlement and habitat choice played an important role in the first and third experiments, and that local transport of recently settled juveniles from the surrounding sediments was important in the second and third experiments. Sandy-site trays had significantly lower diversity than muddy-site trays, but there was no effect of sediment type in trays on diversity of colonizers. These experiments focused on small spatial scales and three short time periods, but they demonstrate that species patterns in some environments may be set by habitat selection by larvae and by juvenile colonization from the surrounding community. Post-colonization processes such as predation and competition likely play a major role for some species, but patterns of initial colonization corresponded well with those in the local community

Temporal and spatial variation in infaunal community structure in physically active continental shelf sediments at a long-term ecosystem observatory (LEO-15) off New Jersey, USA

When the LEO-15 (Long-term Ecosystem Observatory at 15-m depth) research area was designated around Beach Haven Ridge (39°27.69′ N, 74°15.81′ W) in the early 1990\u27s several stations were selected to reflect the different physical regimes and habitats present in a highly dynamic shelf environment. This study determined the composition, diversity, and abundance of infaunal communities at three contrasting stations on five dates in 1994–1995. A unique sampling scheme was used where a nested design was combined with targeted sampling by divers of benthic topographic habitat features, namely crests and troughs of sand ripples. The total number of taxa collected was 148. The majority of taxa (80%) were either ubiquitous (67 taxa, 45%) or had an apparent affinity for a single station (52 taxa, 35%). The polychaete Polygordius jouinae was numerically dominant. The three distinctive stations 2–4 km apart, the date of sampling and, somewhat surprisingly, whether or not samples were taken in adjacent crests or troughs, all contributed to the structure of LEO-15 infaunal communities. Together these three stations characterize the sediments and fauna in the LEO-15 research area and form the basis for future studies of short and longer-term changes, and of the processes and mechanisms responsible for the patterns observed

A natural history of the deep-sea aplacophoran Prochaetoderma yongei and its relationship to confamilials (Mollusca, Prochaetodermatidae)

Author Posting. © The Author(s), 2009. This is the author's version of the work. It is posted here by permission of Elsevier B.V. for personal use, not for redistribution. The definitive version was published in Deep Sea Research Part II: Topical Studies in Oceanography 56 (2009): 1856-1864, doi:10.1016/j.dsr2.2009.05.026.Previously published studies are woven together into a natural history of a deep-sea aplacophoran mollusc species, Prochaetoderma yongei Scheltema, 1985, and its confamilial species in the Prochaetodermatidae. This amphi-Atlantic species occurs in sometimes great numbers at upper bathyal depths, rivaling polychaetes in numerical dominance. It appears to be an opportunist, with wide geographic and depth distribution, rapid development from lecithotrophic larva to settlement and maturity, and omnivory. A short illustrated morphological description using characters useful for identifying all prochaetodermatid species should prove useful to nontaxonomists whose business is the deep-sea benthic fauna

Macrofaunal response to artificial enrichments and depressions in a deep-sea habitat

To test whether colonizing macrofauna specialize on different types of small-scale patches of food and disturbance in the deep sea, sediment tray and artificial depression colonization experiments were conducted on the deep-sea floor at 900-m depth, south of St. Croix, U.S. Virgin Islands. Trays and depressions were unenriched (Unenriched Controls) or enriched with either Thalassiosira sp. or Sargassum sp. Concurrent deployment of different types of enrichment and disturbance made it possible to evaluate whether macrofauna specialize on different patches, and thus avoid species interactions that might lead to competitive exclusion. Depressions create a hydrodynamic regime that traps passive particles, allowing tests of the relative importance of active selection of different patch types versus passive deposition for abundant colonizers. After 23 d, total densities and densities of the four abundant colonizers (Capitella spp., Nereimyra punctata, Cumella sp. and Nebalia sp.) were extremely high in enriched trays, despite relatively low ambient densities. Densities in Unenriched Control Trays were very low, and did not attain ambient densities. After 24 d, total densities in all depression treatments were considerably lower than in enriched tray treatments, and only Sargassum Depression densities exceeded those in the ambient environment. Lower densities of organisms in depression treatments compared with trays and differences in densities among depression treatments suggest that the dominant colonizers were highly active and selective, and were not passively entrained in depressions. Faunal analysis indicated that trays and depressions were very different, and Sargassum Depression fauna was very different from other depression types. A strong difference was not observed between fauna in ambient sediments and Thalassiosira sp. or Unenriched Control Depressions, perhaps because Thalassiosira sp. was dropped in depressions on the sediment surface and may have been more readily available to consumers and more rapidly consumed than in trays. Thalassiosira Trays were colonized by a lower diversity fauna than Sargassum Trays, and Unenriched Control Trays were colonized by very low densities of a fauna that was comparable in diversity to the ambient community. Diversity in Sargassum Depressions was higher than in enriched trays but lower than in other artificial depressions and the ambient fauna. Thalassiosira Depressions and Unenriched Control Depressions were comparable in diversity to ambient fauna and natural depressions, which were highly diverse. These experiments suggest that fauna may respond quickly and selectively to artificial food patches and disturbance, and this fauna is different from that observed in the ambient sediment. Thus, a patch mosaic may be part of the reason for the high species diversity that is observed in deep-sea ecosystems. The different, highly diverse, fauna observed in natural depressions compared with flat ambient sediment suggests that natural analogs of these experiments have unique faunas that may contribute to the species richness of deep-sea habitats