Graduate Position: sea urchin population dynamics in the Gulf of Maine

Project Title: Disentangling the effects of climate change and fishing pressure on sea urchin populations
in the Gulf of Maine

Project overview: Over the last 3 decades, sea urchin (Strongylocentrotus droebachiensis) populations in the Gulf of Maine have experienced precipitous declines in landings and abundance. The height of the
fishery peaked in 1993. Since then, a variety of fishery management regulations and strategies have
been implemented to sustain and recover populations with little success. While fishing pressure most
certainly played a strong role initially, a variety of environmental and ecological factors are likely
interacting to exacerbate declines and preventing the recovery of regional populations.

The aim of this project is to take a holistic approach to evaluate the discrete and combined effects of
climate change drivers, harvest, and ecological relationships on regional sea urchin population
dynamics.

The ME DMR’s fishery-independent surveys and fishery-dependent timeseries data provide a unique
opportunity to evaluate sea urchin population dynamics across decadal and seasonal time periods as
well as across multiple spatial scales. Data span the Gulf of Maine region as a whole, a latitudinal
gradient of fishery management zones, and local quadrat-based depth transects from the spring dive
survey. An archive of harvester interviews also provides additional valuable accounts to provide an
integrated socio-ecological perspective on how sea urchin populations have changed over time.

The project will investigate the effects of long-term (e.g., SST and bottom temperature, salinity, pH) and
seasonal (e.g., spring/fall onset, winter duration and severity) climate drivers on sea urchin population
metrics and reproduction phenology (e.g., abundance, presence/absence, size, roe condition, spawning
timing). We will test hypotheses of whether sea urchin abundance, persistence, and size are more
strongly associated with spatial or temporal changes in regional climate conditions. Once the suite of
potential climate drivers has been reduced to those showing the greatest influence on each population
metric, we will build statistical models that evaluate the relative influence of climate and fishing
pressure (e.g., catch limits and seasonal windows).

A second phase of work will investigate trophic effects on sea urchin population dynamics. Analyses will
evaluate whether other echinoderm species (e.g., sea cucumbers, and sea stars) show similar patterns
of population declines across the region, potentially signaling guild-wide changes consistent with climate
disturbance. Sea urchin occurrence will also be correlated with forage (e.g., macroalgae, kelp), symbiont
(e.g., mussel species), predator (e.g., Jonah crab, Cancer borealis) and competitor species (e.g., nonnative invasive tunicate species) distribution to provide insights into ecological factors that are
influencing sea urchin population recovery.

Position responsibilities:
Applications are invited for a full-time graduate research position to be located at the University of
Maine’s Darling Marine Center in Walpole, Maine. Responsibilities will be to:

• Conduct a literature review of sea urchin responses to environmental and ecological factors.
• Build statistical models that evaluate climate, fishery, and trophic impacts on sea urchin
populations using Generalized Linear Models (GLMs), Generalized Mixed Models (GLMMs),
Generalized Additive Models (GAMs), GIS, and other methods.
• Create data visualizations and summaries that communicate results to technical and nontechnical audiences.
• Work collaboratively with academic and state agency partners.
• Organize meetings, workshops and other engagement activities with project partners.
• Communicate and disseminate results through written reports, meetings with project partners,
and at regional and national scientific meetings.

Qualifications:
• A completed Masters degree by date of hire in Fisheries, Marine Science or related field. Or 2-3
years of experience working at a fisheries management agency or other institution.
• Strong background and interests in ecology, fisheries, and climate adaptation.
• Prior experience, coursework, and training in quantitative methods (statistical models and
spatial analyses) and use of R and Arc GIS.
• Strong organizational and communication skills.
• Ability to work independently and as part of a collaborative team.
• Applicants must be currently authorized to work in the United States on a full-time basis.

Location: Darling Marine Center, Walpole ME

Start date: Fall 2024

How to apply: Email Michelle Staudinger (michelle.staudinger@maine.edu) a 1 page cover letter and
C.V. outlining interest and related experience to the project, confirmation of degree, and anticipated
start date. Applicants will need to apply and be accepted to the UME graduate school for fall 2024. More
information on this process can be found https://umaine.edu/staudingerlab/come-school-with-us/