A review of the opportunities and challenges for using remote sensing for management of surface-canopy forming kelps

© The Author(s), 2021. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Cavanaugh, K. C., Bell, T., Costa, M., Eddy, N. E., Gendall, L., Gleason, M. G., Hessing-Lewis, M., Martone, R., McPherson, M., Pontier, O., Reshitnyk, L., Beas-Luna, R., Carr, M., Caselle, J. E., Cavanaugh, K. C., Miller, R. F., Hamilton, S., Heady, W. N., Hirsh, H. K., Hohman R., Lee L. C., Lorda J., Ray J., Reed D. C., Saccomanno V. R., Schroeder, S. B. A review of the opportunities and challenges for using remote sensing for management of surface-canopy forming kelps. Frontiers in Marine Science, 8, (2021): 753531, https://doi.org/10.3389/fmars.2021.753531.Surface-canopy forming kelps provide the foundation for ecosystems that are ecologically, culturally, and economically important. However, these kelp forests are naturally dynamic systems that are also threatened by a range of global and local pressures. As a result, there is a need for tools that enable managers to reliably track changes in their distribution, abundance, and health in a timely manner. Remote sensing data availability has increased dramatically in recent years and this data represents a valuable tool for monitoring surface-canopy forming kelps. However, the choice of remote sensing data and analytic approach must be properly matched to management objectives and tailored to the physical and biological characteristics of the region of interest. This review identifies remote sensing datasets and analyses best suited to address different management needs and environmental settings using case studies from the west coast of North America. We highlight the importance of integrating different datasets and approaches to facilitate comparisons across regions and promote coordination of management strategies.Funding was provided by the Nature Conservancy (Grant No. 02042019-5719), the U.S. National Science Foundation (Grant No. OCE 1831937), and the U.S. Department of Energy ARPA-E (Grant No. DE-AR0000922)

The distribution and abundance of the California horn snail at different spatial scales

The California horn snail (Cerithidea californica (Haldeman, 1840) (Potamididae: Prosobranchia) dominates the heterotrophic biomass of the salt marsh estuaries of California, Baja California, and Baja California Sur. Thus, it is an ecologically important species, functioning as a significant grazer and competitor, and host to more than 19 species of trematode parasites that infect many other species of invertebrates, fish, and birds as second, intermediate, and final hosts. Any changes in the distribution and abundance of this snail would likely have strong effects throughout estuarine food webs. Here I present observational and experimental studies performed both in the laboratory and in nature that advance our knowledge about the distribution and abundance of these snails. In the first chapter, I show how snail distribution and abundance was restricted by vascular vegetation, bank orientation in channels, and water depth, due to the negative effects of shading on benthic primary production. Vascular vegetation dominates the biomass of the estuaries of California and Baja California, any changes in vegetation cover will subsequently have an effect on the abundance and distribution of snails. In chapter two, I present how crabs negatively affected snails through predation and non-lethal effects that changed the behavior and diminished the growth rates of snails. Predation pressure was especially high on eggs and the smallest size classes of snails, which had been overlooked in previous predation studies. Finally, in chapter three I present results on how low temperature seems likely to set the northern extent of the horn snail's range by reducing snail performance. Results also suggest a possible tradeoff between growth and reproduction and highlight that although temperature might be important, several other local variables such as predator abundance and parasitism also have a considerable effects on snail abundance and performance. Understanding what sets the distribution and abundance of horn snails at local and regional scales will allow us to better predict the effects of climate change and other anthropogenic effects on these estuarine ecosystems

Growth and Body Weight Variability of the Invasive Mussel Limnoperna fortunei (Mytilidae) Across Habitat and Season

The freshwater mussel, Limnoperna fortunei, is adapted to colonize a wide range of aquatic environments, and its ability to contend with environmental stress through phenotypic plasticity has allowed this species to successfully colonize and become established in new regions. Only limited information is currently available on the widely intraspecific variability of this species in response to environmental heterogeneity. Here, we tested the hypotheses that (1) growth and body weight of mussels from a highly polluted environment differed from those from a less polluted habitat, and (2) growth parameters estimated in this study differed from those reported for other invaded ecosystems. We conducted controlled field experiments in two study sites with differing levels of pollution. To compare our results to those reported elsewhere, we considered growth data from studies performed in different locations. We found that mussels from the more polluted habitat showed lower shell growth and body weight than those from the less polluted environment. We also observed differences in the growth performances of the golden mussel between our estimates and those from other invaded habitats. Our findings provide useful information to better understand the striking intraspecific variability of this species in response to stressful conditions. Knowledge on the phenotypic plasticity of L. fortunei is essential for predicting and managing this species.Fil: Bonel, Nicolás. Universidad Nacional del Sur. Departamento de Biología, Bioquímica y Farmacia. Laboratorio de Zoología de Invertebrados I; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Lorda, Julio. University of California; Estados Unido

Differences in density, shell allometry, and growth between two populations of Limnoperna fortunei (Mytilidae) from the Río de La Plata basin, Argentina

The invasive freshwater mussel, the mytilid Limnoperna fortunei (Dunker, 1857), has a great capacity for colonizing a wide range of aquatic environments because of its dispersal ability, high fecundity and wide range of physiological tolerances. Most of the biological and ecological studies of L. fortunei, having been restricted to specific locations, lack comparative analyses among different habitats. In this investigation, we examined the differences in larval density, density in settlement plates, shell allometry, and growth between two populations from the Rio de la Plata basin, Argentina. One of the populations inhabited a heavily polluted area, whereas the other a moderately polluted area. We predicted that the density and growth of the golden mussel would be lower in the heavily polluted environment, expecting therefore to find variations in shell allometry as a consequence of differences in density and environmental conditions between the sites investigated. We accordingly found that the larval density, the density of settled individuals, and the growth were lower in the more polluted environment. We also observed allometric differences because the individuals from the moderately polluted area with higher population densities were more elongated (i.e., with a higher shell length-to-width ratio). The golden mussel tolerates a wide range of environmental conditions and can survive in many polluted water bodies where other invasive species cannot. The findings presented here support the idea that L. fortunei can inhabit heavily polluted environments, but at the expense of a significant decrease in its biologic potential.Fil: Bonel, Nicolás. Universidad Nacional del Sur. Departamento de Biología, Bioquímica y Farmacia. Laboratorio de Zoología de Invertebrados I; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Solari, Lía Cristina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Limnología "Dr. Raúl A. Ringuelet". Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. Instituto de Limnología; ArgentinaFil: Lorda, Julio. University of California at Irvine; Estados Unido

A native-range source for a persistent trematode parasite of the exotic New Zealand mudsnail (Potamopyrgus antipodarum) in France

International audienceThe globally successful invasive snail, Potamopyrgus antipodarum (Tateidae), is rarely parasitized except in its native New Zealand where it is infected as first intermediate host by at least 20 species of trematode parasitic castrators. In France and Poland, only one trematode parasitic castrator, belonging to the Aporocotylidae (the blood flukes of fishes), is known to infect P. antipodarum, and its origin remains a mystery. We investigated the genetic identities, taxonomic relationships, and prevalences of this parasite and other aporocotylids infecting P. antipodarum and closely related snails in a French stream, and throughout New Zealand and southeast Australia. ITS2 DNA sequences of the French parasite matched with Aporocotylid sp. I (sensu Hechinger, 2012) from P. antipodarum in New Zealand. Hence, the aporocotylid parasite in Europe most likely originated from the native range of the introduced host. Aporocotylid sp. I was rare in both native and invasive ranges, infecting overall less than 1 out of 1,000 snails. The parasite and its host have a persistent relationship in France, as they both were repeatedly encountered over a period of 14 years. Our molecular phylogeny also reveals that this parasite is part of a diverse and poorly known group of aporocotylids in New Zealand and southeastern Australia

Sea-level driven glacial-age refugia and post-glacial mixing on subtropical coasts, a palaeohabitat and genetic study.

Using a novel combination of palaeohabitat modelling and genetic mixture analyses, we identify and assess a sea-level-driven recolonization process following the Last Glacial Maximum (LGM). Our palaeohabitat modelling reveals dramatic changes in estuarine habitat distribution along the coast of California (USA) and Baja California (Mexico). At the LGM (approx. 20 kya), when sea level was approximately 130 m lower, the palaeo-shoreline was too steep for tidal estuarine habitat formation, eliminating this habitat type from regions where it is currently most abundant, and limiting such estuaries to a northern and a southern refugium separated by 1000 km. We assess the recolonization of estuaries formed during post-LGM sea-level rise through examination of refugium-associated alleles and approximate Bayesian computation in three species of estuarine fishes. Results reveal sourcing of modern populations from both refugia, which admix in the newly formed habitat between the refuges. We infer a dramatic peak in habitat area between 15 and 10 kya with subsequent decline. Overall, this approach revealed a previously undocumented dynamic and integrated relationship between sea-level change, coastal processes and population genetics. These results extend glacial refugial dynamics to unglaciated subtropical coasts and have significant implications for biotic response to predicted sea-level rise

Microsatellite allele copy number data

allele copy number data for all 3 species used for the genetic Discriminant Function Analysis ('genetic DFA). Microsatellite fragment lengths are alleles, and individuals can have 0 copies of an allele, 1 copy of an allele (heterozygous) or 2 copies of an allele (homozygous)

PRSB_qyc_forDIYABC_3pops

input data file for DIYABC v. 2 for Quietula y-caud