Determinants of the nursery role of seagrass meadows in the sub-tropical Gulf of Mexico: inshore-offshore connectivity for snapper and grouper

Quantifying the nursery role of habitats or locations in supporting fisheries is central to understanding population-scale animal-habitat relationships, and in guiding ecosystem-based management. We assessed the nursery role of northern Gulf of Mexico seagrass meadows for gray snapper, lane snapper, and gag recruiting to Alabama’s extensive offshore reef complex. We accomplished this using broadscale juvenile trawl surveys and geochemical tags—indicative of past habitat use—stored in the otoliths of >2200 fishes. These natural tags revealed that 47-61% of snapper and gag recruits to Alabama reefs originated in Florida panhandle seagrass nurseries. Seagrass meadows in Alabama and Mississippi were also important nurseries for snappers and gag, contributing 26-46% of recruits. Despite high juvenile snapper and gag catches along the extensive Chandeleur Islands, Louisiana, relatively few of those fishes recruited to Alabama’s reefs (<13% of total recruits, across species), although they may have recruited to populations outside our sampling domain. Beyond the applied value of these data for resource management (i.e. interstate connectivity), our findings highlight broadscale drivers of the nursery role of juvenile habitats for coastal marine populations. These factors include: (1) juvenile habitat extent (i.e. extensive Florida panhandle meadows sourced the most recruits for Alabama fisheries); (2) proximity between juvenile and adult habitats (i.e. highest unit-area contribution from Alabama-Mississippi meadows); and (3) unidirectional, alongshore migration of egressing juveniles (i.e. primarily east-to-west movement, enhancing connectivity with Florida panhandle nurseries, and dampening connectivity with Chandeleur nurseries).

Aedes albopictus Body Size Differs Across Neighborhoods With Varying Infrastructural Abandonment

Mosquitoes pose an increasing risk in urban landscapes, where spatial heterogeneity in juvenile habitat can influence fine-scale differences in mosquito density and biting activity. We examine how differences in juvenile mosquito habitat along a spectrum of urban infrastructure abandonment can influence the adult body size of the invasive tiger mosquito, Aedes albopictus (Skuse) (Diptera: Culicidae). Adult Ae. albopictus were collected across 3 yr (2015–2017) from residential blocks in Baltimore, MD, that varied in abandonment level, defined by the proportion of houses with boarded-up doors. We show that female Ae. albopictus collected from sites with higher abandonment were significantly larger than those collected from higher income, low abandonment blocks. Heterogeneity in mosquito body size, including wing length, has been shown to reflect differences in important traits, including longevity and vector competence. The present work demonstrates that heterogeneity in female size may reflect juvenile habitat variability across the spatial scales most relevant to adult Aedes dispersal and human exposure risk in urban landscapes. Previous work has shown that failure to manage abandonment and waste issues in impoverished neighborhoods supports greater mosquito production, and this study suggests that mosquitoes in these same neighborhoods could live longer, produce more eggs, and have different vector potential.

Distribution and Habitat Karakteristics of Shrimp Juvenile in Segara Anakan Lagoon

Shrimp is a wealth of fishery resources are abundant and has a high economic value in Laguna Segara lagoon. So the existence and habitat of life from larvae to adult need attention to maintain the survival of shrimp. Therefore, the purpose of this research is to know the distribution of abundance and characteristics of shrimp juvenile habitat in Segara Anakan lagoon. Sampling is done 3 times (June, August and October 2013), with 9 stations Observation station. The results showed that the abundance of shrimp based on the amount in Segara Anakan lagoon was dominated by Metapenaeus elegans (205-8723 ind./1000 m2), whereas the abundance of M. ensis, F merguensis, P. semisulcatus and P. monodon relatively low had the same habitat , ie waters with high fertility and relatively low salinity, relatively high pH. Found in Motean observation station, Muara Dua, Kleces and Majingklak. Harpiosquilla annandalei (0-330 ind/1000 m2), P. monodon (0-238 ind/1000 m2), and Acetes sp (0.1-5.196 ind/1000 m2) sounded a lot of water habitat that contain BOT and high zooplankton abundance. Thus the shrimp Harpiosquilla annandalei, P. monodon, and Acetes sp are found in Tritih observation stations, and are quite commonly found in Kleces observation stations. Keywords: abundance, habitat preferences, juvenile shrimp, Segara Anakan Lagoon

I Feel That! Fluid Dynamics and Sensory Aspects of Larval Settlement across Scales

A commonality among oceanic life cycles is a process known as settlement, where dispersing propagules transition to the sea floor. For many marine invertebrates, this transition is irreversible, and therefore involves a crucial decision-making process through which larvae evaluate their juvenile habitat-to-be. In this chapter, we consider aspects of the external environment that could influence successful settlement. Specifically, we discuss water flow across scales, and how larvae can engage behaviors to influence where ocean currents take them, and enhance the likelihood of their being carried toward suitable settlement locations. Next, we consider what senses larvae utilize to evaluate their external environment and properly time such behavioral modifications, and settlement generally. We hypothesize that larvae integrate these various external cues in a hierarchical fashion, with differing arrangements being employed across ontogeny and among species. We conclude with a brief discussion of the future promises of larval biology, ecology, and evolution.