Sarah Henkel

• Ph.D.
• Professor (Associate) at Oregon State University

Fishery discards worldwide increase the availability of organic materials on the benthos, altering trophic relationships and potentially increasing the abundance of benthic consumers. Expert knowledge from fishers is a valuable yet often underutilized source of information to understand these dynamics. We interviewed Dungeness crab fishers ( n = 24...

To mitigate the effect of climate change, the demand for marine renewable energy infrastructure is increasing worldwide. These facilities convert the kinetic energy of offshore wind, waves, tides or currents into electricity that is transported to shore through alternating current (AC), or direct current (DC), subsea cables. Energized cables emit m...

Sound is a crucial aspect of the underwater environment for fishes—various species use sound to communicate, identify predators, navigate, and many other activities needed for survival in their habitat. In the summer of 2021, a seismic survey passed nearby Southern Oregon to map the Cascadia Subduction Zone using an array of airguns. To evaluate th...

Dungeness crabs Cancer magister support the largest fishery in Oregon (USA), which inputs millions of pounds of bait into the coastal ocean every year. We assessed evidence for seasonal consumption of commercial Dungeness crab fishery bait off the Oregon coast by that target species through δ ¹³ C and δ ¹⁵ N stable isotope and gut content analysis....

The burrowing ghost shrimp Neotrypaea californiensis and Neotrypaea gigas, are recognized primarily from soft-sediment intertidal mudflats of estuaries and coastal lagoons in the northeastern Pacific from southern Alaska to Baja California. Individual records, however, are also known from occasional deep-water offshore collections. In previous offs...

The "beneficial uses" of dredged sediment are increasingly being explored for habitat restoration and beach nourishment, but beneficial uses must be tempered by evaluating impacts to organisms. We studied a subtidal nearshore deposition site intended to aid beach nourishment where a "thin-layer" sediment deployment method was employed to minimize m...

Point sampling of soft sediment macrofauna was conducted across the shelf and upper slope in the northeastern Pacific Ocean off the United States Pacific Northwest coast to conduct a regional analysis of species composition and use species assemblages to define habitat types. Analyses focused on linking spatial variability in macrofauna assemblages...

This study developed maps of the modeled spatial distributions of deepsea corals, sponges, and benthic macrofauna offshore of the continental US West Coast to 1,200 m depth. Occurrence data for deep-sea corals, sponges, and macrofauna and spatial environmental predictors depicting seafloor topography, substrate, oceanography, and geography were use...

We compared the behavior of Dungeness crabs in an open sandy substrate environment with that of crabs inhabiting an environment of mixed rocky and sandy substrate. The objective was to compare residence time of tagged crabs within range of hydroacoustic receiver arrays. We deployed Vemco acoustic receivers in a complementary design at two sites tha...

This research assessed the effectiveness of benthic video sleds for monitoring the impacts of dredged material disposal on epifauna at shallow and deep water disposal sites near the mouth of the Columbia River, USA. Video sleds collected visual transects at the two disposal sites and comparable reference areas during 2014 and 2015 within a Before-A...

Aim We assessed whether currently described marine biogeographic boundaries apply to shelf macrofauna and which environmental drivers were most associated with species differences among regions. Location Pacific coast of North America from the Strait of Juan de Fuca in Washington to the California–Mexico border. Methods Van Veen grab samples were...

Coastal marine communities face both physical oceanographic changes and altered ecological relationships due to indirect human activities, such as climate-related changes, and direct human activities, such as extraction of wave energy as a renewable resource. Often single physical oceanographic changes and altered ecological relationships are inves...

Environmental assessment studies are usually required by a country's administration before issuing permits for any industrial activities. One of the goals of such environmental assessment studies is to highlight species assemblages and habitat composition that could make the targeted area unique. A section of the Oregon continental slope that had n...

There has been increased enthusiasm to mitigate the negative effects of fossil fuel consumption through the use of cleaner sources of energy, like marine renewable energy (MRE). Concerns about MRE deployments have motivated research on the ecological effects of these new man-made structures in marine environments. We assessed the extent to which so...

With increasing cascading effects of climate change on the marine environment, as well as pollution and anthropogenic utilization of the seafloor, there is increasing interest in tracking changes to benthic communities. Macrofaunal surveys are traditionally conducted as part of pre-incident environmental assessment studies and post-incident monitor...

Resource managers increasingly use habitat suitability map products to inform risk management and policy decisions. Modeling habitat suitability of data-poor species over large areas requires careful attention to assumptions and limitations. Resulting habitat suitability maps can harbor uncertainties from data collection and modeling processes; yet...

Increasing interest in offshore development has motivated intensified efforts to map the seafloor for marine spatial planning. However, surficial geologic maps do not accurately represent habitats for various species groups of concern. This study used a bottom-up approach to integrate macrofaunal densities and benthic conditions on the Pacific Nort...

In 2014 the U.S. Geological Survey (USGS) and the Bureau of Ocean Energy Management (BOEM) entered into Intra-agency agreement M13PG00037 to map an area of the Oregon Outer Continental Shelf (OCS) off of Coos Bay, Oregon, under consideration for development of a floating wind energy farm. The BOEM requires seafloor mapping and site characterization...

Aim Populations of several sea star species were devastated by a disease in 2013–2014 from Alaska to Baja California. However, their exact distributions and ecological requirements are unknown and better knowledge could help identify populations that are at risk. This study aimed to assess patterns of distribution and determine ecological requireme...

As human impacts and demands for ocean space increase (fisheries, aquaculture, marine reserves, renewable energy), identification of marine habitats hosting sensitive biological assemblages has become a priority. Epifaunal invertebrates, especially the structure-forming species, are an increasing conservation concern as many traditional (bottom-con...

Seagrass ecosystems are some of the most productive coastal habitats in the world. Eelgrass (Zostera marina) is an ecosystem engineer that provides important ecosystem functions and services. In 2010, the National Oceanic and Atmospheric Administration (NOAA) began construction of their Marine Operations Center-Pacific (MOC-P) in Yaquina Bay, Orego...

About 55 species of sea stars live on the Pacific Northwest continental shelf. Starting in June 2013 about 20 species suffered from the sea star wasting disease (SSWD) that occurred from Alaska to Baja California. This disease drastically altered population densities and potentially species distributions in most of the intertidal areas. However, se...

As human impacts and demands for ocean space increase (fisheries, aquaculture, marine reserves, renewable energy), identification of marine habitats hosting sensitive biological assemblages has become a priority. Epifaunal invertebrates, especially the structure-forming species, are an increasing conservation concern as many traditional (bottom-con...

A better understanding of the seasonal and spatial distribution of Crangon shrimp and their relationship with their predators, including the green sturgeon, Acipenser medirostris , is an important step toward the larger goal to understand food webs of the nearshore continental shelf of the northeastern Pacific. Here, I examined how the biomass and...

The wave and wind climates along the west coast of North America provide some of the best prospects for offshore renewable energy development, yet initial assessments of the seafloor have been patchy. The Bureau of Ocean Energy Management (BOEM) requires knowledge of the seafloor environment and of seafloor-associated (benthic) organisms that may b...

The wave and wind climates along the west coast of North America provide some of the best prospects for offshore renewable energy development, yet initial assessments of the seafloor have been patchy. The Bureau of Ocean Energy Management (BOEM) requires knowledge of the seafloor environment and of seafloor-associated (benthic) organisms that may b...

Mitigating for increased human impact in US coastal waters associated with offshore renewable energy device deployment requires an understanding of the distribution of sensitive marine benthic species. For managers to make informed decisions that advance societal development while lessening the impact on species of interest, integrative models that...

The wave climate along the west coast of North America presents great opportunities for the development of offshore renewable energy, yet initial assessments of the potential ecological effects of wave energy development have only just started. An enhanced regional understanding of the biological resources in the area is needed, and a key informati...

Background / Purpose: This work is aimed at using dead seashells to collect historical information about the benthic communities off the coast of Newport, Oregon. Modern monitoring efforts have extensive data on presence/absence and abundances of living bivalve assemblages that are references for the accuracy of death assemblages. Main conclusio...

A number of review articles have synthesized current expert opinion regarding interactions of ocean energy generation technologies with environmental parameters and their potential effects and impacts. Fewer articles have documented such interactions, as operational devices and or demonstration sites at which to make such observations are limited....

This project examined the information needs of those interested in the planning for marine renewable energy in Oregon. The objective was to recommend to Oregon State University’s Northwest National Marine Renewable Energy Center (NNMREC) an approach to facilitating sharing of relevant information concerning marine renewable energy in Oregon and Was...

While the coastal waters of western North America hold great potential for offshore renewable energy development, concerns have been raised about the effects to benthic habitat and organisms by the installation of devices and complex mooring systems. However, little is known about natural species-habitat relationships and community processes in dep...

The transboundary nature of global environmental change demands collaborative, multiscale, interdisciplinary research [U.S. National Academy of Sciences, 2005]. This requires ``a new kind of scientist'' [Schmidt and Moyer, 2008]; collaborators must develop both sufficient understanding of one another's work and the skills to integrate data sets and...

This study characterized the response to thermal stress in 3 kelp species to contribute to the un- derstanding of the role of the heat shock response in species distributions and in native-invasive species in- teractions. We sampled the invasive kelp Undaria pin- natifida in its native range in Japan and its introduced range in California, USA, to...

Temperature is one of the primary factors determining the geographic boundaries of seaweeds. Thus, investigations of how seaweeds cope with temperature stress and what affects their ability for range expansion are particularly important when studying invasive species. In physiological ecology, an established index of thermotolerance is the up-regul...

Given the ecological and economic impact of invasive species, knowledge of traits that allow the invasive kelp Undaria pinnatifida (Harvey) Suringar to expand its range is important for developing prevention and eradication efforts. Physiological mechanisms of thermotolerance may be important as they can influence both local and regional patterns o...

Sea breezes often have significant impacts on nearshore physical and biological processes. We document the effects of a diurnal sea breeze on the nearshore thermal structure and circulation of northern Monterey Bay, California, using an array of moorings during the summer upwelling season in 2006. Moorings were equipped with thermistors and Acousti...

This study characterized morphological variation in the kelp, Egregia menziesii, over a large geographic scale. Marked differences in rachis and lateral blade morphology were observed, suggesting local adaptation to the variable conditions of wave exposure and upwelling found across the study area. Observations of rachis type at different developme...

Intertidal Egregia menziesii (Turner) Aresch. populations were studied at three Southern California sites to determine temporal and spatial patterns of reproduction and morphology. The timing of sporophyll production and sporophyte recruitment was similar at all sites. Sporophyll production was much greater during winter periods of colder seawater...

Egregia menziesii is a complex kelp with an adult morphology that varies considerably across its geographic range. Fertility in Egregia also varies geographically. We studied intertidal populations of Egregia at three southern California sites to determine spatial and temporal patterns of reproduction, recruit-qment, and morphology. Growing axes of...