Peter V. August

Coastal Lagoons and Climate Change: Ecological and Social Ramifications in U.S. Atlantic and Gulf Coast Ecosystems

Lagoons are highly productive coastal features that provide a range of natural services that society values. Their setting within the coastal landscape leaves them especially vulnerable to profound physical, ecological, and associated societal disturbance from global climate change. Expected shifts in physical and ecological characteristics range from changes in flushing regime, freshwater inputs, and water chemistry to complete inundation and loss and the concomitant loss of natural and human communities. Therefore, managing coastal lagoons in the context of global climate change is critical. Although management approaches will vary depending on local conditions and cultural norms, all management scenarios will need to be nimble and to make full use of the spectrum of values through which society views these unique ecosystems. We propose that this spectrum includes pragmatic, scholarly, aesthetic, and tacit categories of value. Pragmatic values such as fishery or tourism revenue are most easily quantified and are therefore more likely to be considered in management strategies. In contrast, tacit values such as a sense of place are more difficult to quantify and therefore more likely to be left out of explicit management justifications. However, tacit values are the most influential to stakeholder involvement because they both derive from and shape individual experiences and beliefs. Tacit values underpin all categories of social values that we describe and can be expected to have a strong influence over human behavior. The articulation and inclusion of the full spectrum of values, especially tacit values, will facilitate and support nimble adaptive management of coastal lagoon ecosystems in the context of global climate change.

Mammal Sounds and Motivation-Structural Rules: A Test of the Hypothesis

We tested if mammal sounds given in aggressive and fearful/friendly contexts showed acoustic design characteristics in accordance with the Motivation-Structural (MS) rule hypothesis (Morton, 1977). Our data were taken from literature and consist of 76 aggressive sounds and 75 fearful/friendly sounds from 50 species of mammals. Aggressive sounds are of low-frequency and wide bandwidth and thus support MS rule predictions. Fearful/friendly sounds show a trend toward conforming to MS rule design expectations (high-frequency and tonal) but exhibit considerable variation. This variation may be due to the existence of acoustic parameters other than frequency or bandwidth that might convey motivation information in fearful/friendly contexts. In addition, fear and friendliness represent two very different motivation states in mammals and MS rules may not apply to both.

Relationships between watershed stressors and sediment contamination in Chesapeake Bay estuaries

Three methods for assessing the relationships between estuarine sediment contaminant levels and watershed Stressors for 25 Chesapeake Bay sub-estuaries were compared. A geographic information system (GIS) was used to delineate watersheds for each sub-estuary and analyze land use pattern (area and location of developed, herbaceous and forested land) and point source pollution (annual outflow and contaminant loading) using three landscape analysis methods: (1) a watershed approach using the watershed of the estuary containing the sampling station. (2) a ‘partial watershed’ approach using the area of the watershed within a 10 km radius of the sampling station and (3) a ‘weighted partial watershed’ approach where Stressors within the partial watershed were weighted by the inverse of their linear distance from the sampling station. Nine sediment metals, 16 sediment organics and seven metals loading variables were each reduced to one principal component for statistical analyses. Relationships between the first principal components for sediment metals and organics concentrations and watershed stressor variables were analyzed using rank correlation and stepwise multiple regression techniques. For both metals and organics, the watershed method yieldedR2 values considerably lower than the partial and weighted partial watershed analysis methods. Regression models using Stressor data generated by the weighted partial watershed landscape analysis method explained 76% and 47% of the variation in the first principal component for sediment metals and organics concentrations, respectively. Results suggest that the area of developed land located in the watershed within 10 km of the sediment sampling station is a major contributing factor in the sediment concentrations of both metals and organics.

Assessing the Accuracy of National Land Cover Dataset Area Estimates at Multiple Spatial Extents

Site-specific accuracy assessments evaluate fine-scale accuracy of land-use/land-cover (LULC) datasets but provide little insight into accuracy of area estimates of LULC classes derived from sampling units of varying size. Additionally, accuracy of landscape structure metrics calculated from area estimates cannot be determined solely from site-specific assessments. We used LULC data from Rhode Island and Massachusetts as reference to determine the accuracy of area measurements from the National Land Cover Dataset (NLCD) within spatial units ranging from 0.1 to 200 km 2 . When regressed on reference area, NLCD area of developed land, agriculture, forest, and water had positive linear relationships with high r2, suggesting acceptable accuracy. However, many of these classes also displayed mean differences (NLCD - REFERENCE), and linear relationships between the NLCD and reference were not one-to-one (i.e., low r 2 , β 0 ¬= 0, β 1 ¬= 1), suggesting mapped area is different from true area. Rangeland, wetland, and barren were consistently, poorly classified.

Magnetic Orientation In A Small Mammal, Peromyscus Leucopus

We displaced white-footed mice ( Peromyscus leucopus ) 40 m away from their home areas and released them in a circular arena. Mice concentrated their exploratory and escape activity in the portion of the arena corresponding to home direction. In another group of mice, we reversed the horizontal component of the geomagnetic field surrounding them during displacement. These individuals concentrated their activity in areas of the circular arena opposite home direction. Mice were not likely using visual, chemical, or kinesthetic cues to establish home direction. Tissues of P. leucopus exhibit strong isothermal remanent magnetization and may contain biogenic ferrimagnetic material. Our results suggest that white-footed mice have a magnetic sense and use the geomagnetic field as a compass cue.

Assessment of Inundation Risk from Sea Level Rise and Storm Surge in Northeastern Coastal National Parks

ABSTRACT Murdukhayeva, A.; August, P.; Bradley, M.; LaBash, C., and Shaw, N., 2013. Assessment of inundation risk from sea level rise and storm surge in northeastern coastal national parks. Sea level rise and an increase in storm frequency and intensity are two major impacts expected to result from climate change in coastal ecosystems. Coastal national parks have many low-lying areas that are at risk from inundation resulting from these impacts. To help park managers meet their goal of preserving resources, we developed a methodology to evaluate risk of inundation from sea level rise and storm surge at sentinel sites, areas of importance for natural, cultural, and infrastructural resources. We selected the most recent, readily available, and appropriate geospatial tools, models, and data sets to conduct case studies of our coastal inundation risk assessments in two northeastern coastal national parks—Cape Cod National Seashore, MA, and Assateague Island National Seashore, MD/VA. We collected elevation data at sentinel sites using real-time kinematic global positioning system (RTK GPS) technology. We used three modeling approaches: modified bathtub modeling; the Sea Level Affecting Marshes Model (SLAMM); and the Sea, Lake, and Overland Surges from Hurricanes (SLOSH) model to assess the likelihood of inundation at sentinel sites. Cape Cods sentinel sites, which in many cases occurred in high-elevation settings, were found to be less vulnerable to inundation than were Assateague Islands sentinel sites, which were distributed in low-lying areas along the barrier beach island. This inundation risk assessment methodology can be applied to other coastal areas and to the same coastal parks at different times as more accurate elevation data sets and updated sea level rise projections become available.

Effects of spatial extent on landscape structure and sediment metal concentration relationships in small estuarine systems of the United States’ Mid-Atlantic Coast

Prior studies exploring the quantitative relationship between landscape structure metrics and the ecological condition of receiving waters have used a variety of sampling units (e.g., a watershed, or a buffer around a sampling station) at a variety of spatial scales to generate landscape metrics resulting in little consensus on which scales best describe land-water relationships. Additionally, the majority of these studies have focused on freshwater systems and it is not clear whether results are transferable to estuarine and marine systems. We examined how sampling unit scale controls the relationship between landscape structure and sediment metal concentrations in small estuarine systems in the Mid-Atlantic region of the United States. We varied the spatial extent of the contributing watersheds used to calculate landscape structure and assessed linear relationships between estuarine sediment metal concentrations and the total area of developed and agricultural lands at each scale. Area of developed lands was consistently related to sediment metals while total agricultural land was not. Developed land had strongest associations with lead and copper; weakest with arsenic and chromium; and moderate associations with cadmium, mercury, and zinc. Local (i.e., less than 15−20 km from a sampling station) land uses have a greater impact than more distant land uses on the amount of toxic metals reaching estuarine sediments.

Modeling Habitat Associations for the Common Loon ( Gavia immer ) at Multiple Scales in Northeastern North America

Common Loon (Gavia immer) is considered an emblematic and ecologically important example of aquatic-dependent wildlife in North America. The northern breeding range of Common Loon has contracted over the last century as a result of habitat degradation from human disturbance and lakeshore development. We focused on the state of New Hampshire, USA, where a long-term monitoring program conducted by the Loon Preservation Committee has been collecting biological data on Common Loon since 1976. The Common Loon population in New Hampshire is distributed throughout the state across a wide range of lake-specific habitats, water quality conditions, and levels of human disturbance. We used a multiscale approach to evaluate the association of Common Loon and breeding habitat within three natural physiographic ecoregions of New Hampshire. These multiple scales reflect Common Loon-specific extents such as territories, home ranges, and lake-landscape influences. We developed ecoregional multiscale models and compared them to single-scale models to evaluate model performance in distinguishing Common Loon breeding habitat. Based on information-theoretic criteria, there is empirical support for both multiscale and single-scale models across all three ecoregions, warranting a model-averaging approach. Our results suggest that the Common Loon responds to both ecological and anthropogenic factors at multiple scales when selecting breeding sites. These multiscale models can be used to identify and prioritize the conservation of preferred nesting habitat for Common Loon populations. RESUME. Le Plongeon huard (Gavia immer) est considere comme un representant emblematique et ecologiquement important de la faune dependante du milieu aquatique en Amerique du Nord. L’aire de reproduction du Plongeon huard a subi une contraction depuis le siecle passe en raison de la degradation de son habitat consecutive au derangement humain et a l’augmentation de l’occupation humaine sur les bords de lacs. Nous avons choisi le cas du New Hampshire, E.-U., car il y existe un programme de suivi a long terme effectue par le Loon Preservation Committee, qui collige les donnees biologiques sur l’espece depuis 1976. La population du Plongeon huard est repartie partout dans cet Etat, selon une grande variete de milieux lacustres, de conditions de qualite d’eau et de degres de derangement humain. Nous avons utilise une approche multi-echelles afin d’evaluer la relation entre le Plongeon huard et son habitat de nidification, dans trois ecoregions physiographiques naturelles au New Hampshire. Ces differentes echelles refletent d’autres caracteristiques relatives au Plongeon huard, comme les territoires, les domaines vitaux et les influences lac-paysage. Nous avons elabore des modeles multi-echelles ecoregionaux et les avons compares a des modeles tenant compte d’une seule echelle pour evaluer leur performance a distinguer correctement l’habitat de nidification du Plongeon huard. D’apres les criteres de la theorie de l’information, les observations empiriques soutiennent les modeles multi-echelles tout comme les modeles a une seule echelle, dans les trois ecoregions, resultat qui justifie une approche fondee sur la moyenne des modeles. Nos resultats U.S. Environmental Protection Agency, Atlantic Ecology Division, SRA International Inc., The Loon Preservation Committee, BioDiversity Research Institute, University of Rhode Island Department of Natural Resources Coastal Institute in Kingston Avian Conservation and Ecology 6(1): 4 http://www.ace-eco.org/vol6/iss1/art4/ laissent croire qu’au moment de selectionner son site de nidification, le Plongeon huard reagit tout autant aux facteurs ecologiques qu’aux facteurs anthropiques, a differentes echelles. Il est possible d’utiliser ces modeles multi-echelles pour determiner l’habitat de nidification de predilection des populations de Plongeon huard et pour en prioriser la conservation.

Mapping Shallow Coastal Ecosystems: A Case Study of a Rhode Island Lagoon

Abstract In order to effectively study, manage, conserve, and sustain shallow-subtidal ecosystems, a spatial inventory of the basic resources and habitats is essential. Because of the complexities of shallow-subtidal substrates, benthic communities, geology, geomorphology, and water column attributes, few standard protocols are fully articulated and tested that describe the mapping and inventory processes and accompanying interpretations. In this paper, we describe a systematic approach to map Rhode Islands shallow-subtidal coastal lagoon ecosystems, by using, integrating, and reconciling multiple data sets to identify the geology, soils, biological communities, and environments that, collectively, define each shallow-subtidal habitat. We constructed maps for these lagoons via a deliberate, step by step approach. Acoustics and geostatistical modeling were used to create a bathymetric map. These data were analyzed to identify submerged landforms and geologic boundaries. Geologic interpretations were verified with video and grab samples. Soils were sampled, characterized, and mapped within the context of the landscape and geologic boundaries. Biological components and distributions were investigated using acoustics, grab samples, video, and sediment profile images. Data sets were cross-referenced and ground-truthed to test for inconsistencies. Maps and geospatial data, with Federal Geographic Data Committee (FGDC)-compliant metadata, were finalized after reconciling data set inconsistencies and made available on the Internet. These data allow for classification in the revised Coastal and Marine Ecological Classification Standard (CMECS). With these maps, we explored potential relationships among and between physical and biological parameters. In some cases, we discovered a clear match between habitat measures; in others, however, relationships were more difficult to distinguish and require further investigation.

Predicting estuarine sediment metal concentrations and inferred ecological conditions: an information theoretic approach.

Empirically derived relationships associating sediment metal concentrations with degraded ecological conditions provide important information to assess estuarine condition. Resources limit the number, magnitude, and frequency of monitoring activities to acquire these data. Models that use available information and simple statistical relationships to predict sediment metal concentrations could provide an important tool for environmental assessment. We developed 45 predictive models for the total concentrations of copper, lead, mercury, and cadmium in estuarine sediments along the Southern New England and Mid-Atlantic regions of the United States. Using information theoretic model-averaging approaches, we found total developed land and percent silt/clay of estuarine sediment were the most important variables for predicting the presence of all four metals. Estuary area, river flow, tidal range, and total agricultural land varied in their importance. The model-averaged predictions explained 78.4, 70.5, 56.4, and 50.3% of the variation for copper, lead, mercury, and cadmium, respectively. Overall prediction accuracies of selected sediment benchmark values (i.e., effects ranges) were 83.9, 84.8, 78.6, and 92.0% for copper, lead, mercury, and cadmium, respectively. Our results further support the generally accepted conclusion that sediment metal concentrations are best described by the physical characteristics of the estuarine sediment and the total amount of urban land in the contributing watershed. We demonstrated that broad-scale predictive models built from existing monitoring data with information theoretic model-averaging approaches provide valuable predictions of estuarine sediment metal concentrations and show promise for future environmental modeling efforts in other regions.