Daily Patterns of River Herring (\u3cem\u3eAlosa\u3c/em\u3e spp.) Spawning Migrations: Environmental Drivers and Variation among Coastal Streams in Massachusetts

The timing of life history events in many plants and animals depends on the seasonal fluctuations of specific environmental conditions. Climate change is altering environmental regimes and disrupting natural cycles and patterns across communities. Anadromous fishes that migrate between marine and freshwater habitats to spawn are particularly sensitive to shifting environmental conditions and thus are vulnerable to the effects of climate change. However, for many anadromous fish species the specific environmental mechanisms driving migration and spawning patterns are not well understood. In this study, we investigated the upstream spawning migrations of river herring Alosa spp. in 12 coastal Massachusetts streams. By analyzing long-term data sets (8–28 years) of daily fish counts, we determined the local influence of environmental factors on daily migration patterns and compared seasonal run dynamics and environmental regimes among streams. Our results suggest that water temperature was the most consistent predictor of both daily river herring presence–absence and abundance during migration. We found inconsistent effects of streamflow and lunar phase, likely due to the anthropogenic manipulation of flow and connectivity in different systems. Geographic patterns in run dynamics and thermal regimes suggest that the more northerly runs in this region are relatively vulnerable to climate change due to migration occurring later in the spring season, at warmer water temperatures that approach thermal maxima, and during a narrower temporal window compared to southern runs. The phenology of river herring and their reliance on seasonal temperature patterns indicate that populations of these species may benefit from management practices that reduce within-stream anthropogenic water temperature manipulations and maintain coolwater thermal refugia

Allergen specificity of early peanut consumption and effect on development of allergic disease in the Learning Early About Peanut Allergy study cohort

BACKGROUND: Early introduction of dietary peanut in high-risk infants with severe eczema, egg allergy, or both prevented peanut allergy at 5 years of age in the Learning Early About Peanut Allergy (LEAP) study. The protective effect persisted after 12 months of avoiding peanuts in the 12-month extension of the LEAP study (LEAP-On). It is unclear whether this benefit is allergen and allergic disease specific. Objective: We sought to assess the effect of early introduction of peanut on the development of allergic disease, food sensitization, and aeroallergen sensitization. METHODS: Asthma, eczema, and rhinoconjunctivitis were diagnosed based on clinical assessment. Reported allergic reactions and consumption of tree nuts and sesame were recorded by questionnaire. Sensitization to food allergens and aeroallergens was determined by means of skin prick testing and specific IgE measurement. RESULTS: A high and increasing burden of food allergen and aeroallergen sensitization and allergic disease was noted across study time points; 76% of LEAP participants had at least 1 allergic disease at 60 months of age. There were no differences in allergic disease between LEAP groups. There were small differences in sensitization and reported allergic reactions for select tree nuts, with levels being higher in the LEAP consumption group. Significant resolution of eczema and sensitization to egg and milk occurred in LEAP participants and was not affected by peanut consumption. CONCLUSION: Early consumption of peanut in infants at high risk of peanut allergy is allergen specific and does not prevent the development of other allergic disease, sensitization to other food allergens and aeroallergens, or reported allergic reactions to tree nuts and sesame. Furthermore, peanut consumption does not hasten the resolution of eczema or egg allergy

Multiple paternity in a viviparous toad with internal fertilisation

Anurans are renowned for a high diversity of reproductive modes, but less than 1% of species exhibit internal fertilisation followed by viviparity. In the live bearing West African Nimba toad (Nimbaphrynoides occidentalis), females produce yolk-poor eggs and internally nourish their young after fertilisation. Birth of fully developed juveniles takes place after nine months. In the present study, we used genetic markers (eight microsatellite loci) to assign the paternity of litters of 12 females comprising on average 9.7 juveniles. In nine out of twelve families (75%) a single sire was sufficient; in three families (25%) more than one sire was necessary to explain the observed genotypes in each family. These findings are backed up with field observations of male resource defence (underground cavities in which mating takes place) as well as coercive mating attempts, suggesting that the observed moderate level of multiple paternity in a species without distinct sperm storage organs is governed by a balance of female mate choice and male reproductive strategies

Environmental DNA analysis of river herring in Chesapeake Bay: A powerful tool for monitoring threatened keystone species.

Environmental DNA (eDNA) sampling has emerged as a powerful tool to detect and quantify species abundance in aquatic environments. However, relatively few studies have compared the performance of eDNA-based abundance estimates to traditional catch or survey approaches in the field. Here, we have developed and field-tested a qPCR assay to detect eDNA from alewife and blueback herring (collectively known as 'river herring'), comparing eDNA-based presence and abundance data to traditional methods of quantification (ichthyoplankton sampling and adult observations). Overall, the qPCR assay showed very high target specificity in lab trials, and was successful in detecting river herring for 11/12 Chesapeake Bay tributaries in spring 2015 and 2016, with 106 out of 445 samples exhibiting positive eDNA hits. We found a strong correlation between eDNA abundance and ichthyoplankton count data (Spearman's Rho = 0.52), and Phi-tests (correlation of presence/absence data) showed higher correlation between eDNA and ichthyoplankton data (Phi = 0.45) than adult data (Phi = 0.35). Detection probability was significantly lower on western vs. eastern shore tributaries of Chesapeake Bay, and blueback herring and alewife were more likely detected on the western and eastern shores, respectively. Temporal patterns of eDNA abundance over the spring spawning season revealed that alewife were present in high abundances weeks ahead of blueback herring, which aligns with known differences in spawning behavior of the species. In summary, the eDNA abundance data corresponded well to other field methods and has great potential to assist future monitoring efforts of river herring abundance and habitat use

Evaluating Community Partnerships Addressing Community Resilience in Los Angeles, California

Community resilience has grown in importance in national disaster response and recovery efforts. However, measurement of community resilience, particularly the content and quality of relationships aimed at improving resilience, is lacking. To address this gap, we used a social network survey to measure the number, type, and quality of relationships among organizations participating in 16 coalitions brought together to address community resilience in the Los Angeles Community Disaster Resilience project. These coalitions were randomized to one of two approaches (community resilience or preparedness). Resilience coalitions received training and support to develop these partnerships and implement new activities. Both coalition types received expert facilitation by a public health nurse or community educator. We also measured the activities each coalition engaged in and the extent to which partners participated in these activities at two time points. We found that the community resilience coalitions were initially larger and had lower trust among members than the preparedness communities. Over time, these trust differences dissipated. While both coalitions grew, the resilience community coalitions maintained their size difference throughout the project. We also found differences in the types of activities implemented by the resilience communities; these differences were directly related to the trainings provided. This information is useful to organizations seeking guidance on expanding the network of community-based organizations that participate in community resilience activities

Environmental DNA reveals anadromous river herring habitat use and recolonization after restoration of aquatic connectivity

Abstract Restoring and sustaining anadromous fish populations is a grand challenge in the conservation of freshwater ecosystems. Alewife Alosa pseudoharengus and Blueback Herring Alosa aestivalis are two closely related anadromous fish for which responses to fish passage restoration are poorly known. We used a targeted environmental DNA method to sample 17 major tributaries of the Chesapeake Bay, USA, to determine the spatial extent of habitat use during the spawning season and the associations of habitat use with watershed characteristics. To help understand responses to restoration of fish passage, the study included portions of eight watersheds where dam removals, fish ladders, or dam failures provided access to habitats that were previously inaccessible to anadromous fish. Overall, 27.5% of samples showed positive detections for river herring, including at least one sample in 16 of 17 tributaries sampled. The presence of both species combined was negatively associated with elevation (relative influence [RI] = 29.8%) and positively associated with a watershed area (RI = 14.5%) and percent cropland (13.6%) of the watershed. In species‐specific analyses, both Alewife (RI = 24.8%) and Blueback Herring (26.2%) presence was negatively associated with elevation, Alewife were more common in watersheds with high percentages of cropland (RI = 19.1%), whereas Blueback Herring were more common in streams with large watersheds (23.2%). The use of formerly blocked spawning habitats was generally greater upstream of sites where dams were removed (2%–100% of habitat used) compared with sites where fish ladders were installed (0%–66.8% of habitat used). The broad‐scale sampling enabled by eDNA methods made it possible to identify habitat use patterns that can be applied to prioritize future restoration efforts and predict species‐specific responses