New Article: Interdisciplinary efforts to explain fish larval dispersal

In a recent study published in Marine Ecology Progress Series, we combine field surveys, genetic analysis and biophysical modelling to explain larval dispersal of convict surgeonfish (Acanthurus triostegus) on the windward coast of O‘ahu, Hawai‘i. Results from the various methods show that Kāne‘ohe Bay acts as a retention zone for the larvae.

The study was led by Chelsie Counsell with colleagues at the University of Hawai‘i at Mānoa in both Biology and Oceanography.

Counsell, C.W.W., R.R. Coleman, S.S. Lal, B.W. Bowen, E.C. Franklin, A.B. Neuheimer, B.S. Powell, R.J. Toonen, M.J. Donahue, M.A. Hixon & M.A. McManus. 2022. Opening the black box: interdisciplinary analysis of larval dispersal for a coral reef fish. Marine Ecology Progress Series. 684: 117-132. (pdf).

New Article: Thermal time predicts growth and development in lobsters and crabs

In a new study published in the Canadian Journal of Fisheries and Aquatic Sciences, we use thermal time to explain growth and development in 7 species of lobsters and crabs. We estimate growing degree-days as a physiologically relevant measure of time for the ectothermic organisms. The models can be used to predict growth under variable temperatures (e.g. in the field), identify temperature tolerance limits, and disentangle temperature effects from other factors affecting growth. The study was led by Dalhousie student Reid W. Steele.

Read more here:

Steele, R. & A.B. Neuheimer. 2022. Assessing the ability of the growing degree-day metric to explain variation in size-at-age and age at moult of lobsters and crabs. Canadian Journal of Fisheries and Aquatic Sciences. (link)

New Article: Life history constraints on fish distribution

Results from our study exploring bottlenecks on fish distribution was published earlier this year in Fish and Fisheries. The study identifies spatial constraints to population distribution at early life stages by characterizing both the consistency and extent of distribution with life stage. The effort explored six groundfish species across three marine systems and can be used to predict limitations to distribution shifts in response to climate change. The study was led by Lorenzo Ciannelli with collaborators Norway, Canada, USA and Russia.

Read more here:

Ciannelli, L. A.B. Neuheimer, L.C. Stige, K.T. Frank, J.M. Durant, M. Hunsicker, L.A. Rogers, S. Porter, G. Ottersen, & N.A. Yaragina. 2002. Ontogenetic spatial constraints of sub-arctic marine fish species. Fish and Fisheries. 23: 342-357. (link)

Neuheimer Lab Qualifying Exam - Good Luck, Kris-Emil!

Kris-Emil Mose Jørgensen’s PhD Qualifying Exam will be held tomorrow (d. 09/11) with the title:

“Spatiotemporal spawning variation in temperate waters. Investigating the who, when and where of fish spawning in Kattegat“

More information here.

Many thanks to the external examiner Prof. Dr. Christian Möllmann for making the trip from the University of Hamburg, co-advisor Prof. Peter Grønkjær, and AU’s Aarhus Institute of Advanced Studies for providing the beautiful location. Kris-Emil’s project is partly funded by the Aarhus Universitets Forskningsfond.

In the field: 2021 larval fish cruises

Our larval fish cruises were featured on AU’s Forskning (Research) website. More info here:

https://bio.au.dk/forskning/forskningsinfrastruktur/forskningsskibet-aurora/fiskelarveundersoegelse-ombord-paa-aurora/

Neuheimer Lab @ Sea - observing larval fish timing in the Kattegat

The Neuheimer Lab is running a series of cruises this spring to observe the timing of larval fish in the Kattegat Sea. Led by PhD Candidate Kris-Emil Jørgensen, we’ve planned six 4-day cruises using AU’s RV AURORA to sample larval Atlantic cod and their copepod prey. Results to follow!

New Article: Exploring the drivers of deep-sea fish growth

Results of our study exploring the drivers of fish growth across habitat depths was published this month in Marine Ecology Progress Series. Led by Jesse Black and Jeff Drazen (the University of Hawaiʻi), the article explores growth in 53 species of teleosts ranging in habitat depth from 0-4000m. We find temperature is a significant driver of growth and identify temperature-independent growth trends with depth. The study was a collaboration between the U.S.A’s University of Hawaiʻi, New Zealand’s National Institute of Water & Atmospheric Research (NIWA), and Denmark’s Aarhus University. Our article was chosen by the editor to be a Feature Article and is available with open-access here.

New Article: Long-term presence of the island-mass effect at Rangiroa Atoll

In an article published this month in Frontiers of Marine Science, we find evidence of long-term presence of the island-mass effect via observations of chlorophyll enhancement around Rangiroa Atoll. The study, led by the McManus lab at the University of Hawaiʻi at Mānoa finds phytoplankton enhancement as high as 130% in nearshore waters over ~ 76% of the study period. We suggest the enhancement is linked to tides and waves transporting the nutrient-rich water from inside Rangiroa’s lagoon to coastal ocean waters. The study is a collaboration with colleagues at University of Hawaiʻi at Mānoa, NOAA’s Pacific Islands Fisheries Science Center, and Aarhus University. Read more about the study here.

New Article: Identifying growth rate differences in Atlantic cod ecotypes

In a recent publication in Marine Ecology Progress Series, we use otoliths to identify juvenile growth rate differences in co-existing ecotypes of Atlantic cod. We find faster growth in North Sea vs. fjord ecotype cod associated associated with the period following settlement. The manuscript was led by Kris-Emil Jørgensen and Peter Grønkjær’s Fish Ecology Lab and was a collaboration between AU and Norway’s Institute for Marine Research (P.E. Jorde) and University of Agder (H. Knutsen). More information can be found here.

New PhD Course - Exploring your Hypotheses with Statistics

Anna is offering a new PhD course this fall entitled “Exploring your Hypotheses with Statistics” through AU’s Department of Biology. Email Anna for more information.

New PhD Course - Productive writing for Biologists

Along with colleagues at AU’s Departments of Bioscience (Johnna Michelle Holding) & Biology (Chris Selbach), Anna will be offering a course entitled Productive Writing for Biologists (1 ECTS).

In this course, students will learn and practice strategies to improve productivity of their scientific writing. The course aims at helping students identify individual strengths and challenges in their scientific writing, and provides them with a range of strategies to develop their writing skills. Students will practice productive writing techniques with their thesis projects.

At the end of the course, the student should be able to:

• identify their personal strengths and weaknesses in their scientific writing.

• use specific productive writing techniques to overcome challenges (organization, creative blocks, endurance).

• work more confidently and productively on the writing tasks of their MSc and PhD projects.

Contact Anna for more information.

Join us in Denmark - 2 year postdoc position available!

There is a 2-year postdoctoral position available in the lab! Come explore your research interests related to seasonal timing of zooplankton and/or fish, e.g.:

• Explaining variability in migration, spawning, settlement and/or larval timing

• Exploring variability in timing controls across trophic levels

• Exploring implications of timing variability for population abundance, persistence, distribution and/or connectivity

Our group strives to provide a safe, equitable, inclusive, and inspiring research environment. Without a diversity of skills and experiences, the scientific community is unable to identify and solve complex problems. In keeping with AU goals, we welcome members irrespective of race, religion, gender identification, sexual orientation, age, or disability status and appreciate diverse perspectives. A core value of our group is research integrity (including honesty and transparency) and we act in accordance with the Policy for Research Integrity, Freedom of Research and Responsible Conduct of Research at Aarhus University.

Click here for more information about the position, and send any questions to Anna here.

Deadline to apply: 30 October 2020.

New article: Evidence for long-term seamount-induced chlorophyll enhancements

In an article published today in Scientific Reports, we identify the probability and magnitude of chlorophyll enhancements around seamounts. Our study shows seamount-induced chlorophyll enhancements (SICE) are most often associated with shallow (<100 m), low-latitude seamounts. SICE seamounts show chlorophyll enhancements of up to 56% relative to open-ocean waters and are associated with higher fisheries catch relative to non-SICE seamounts.

The study was led by Dr. Astrid Leitner (Monterey Bay Aquarium Research Institute) and in collaboration with Dr. Jeffrey Drazen (University of Hawai’i at Mānoa). The work was supported by a Denise B. Evans Research Fellowship funded by the University of Hawai’i’s School of Ocean and Earth Science and Technology and Department of Oceanography, as well as an Aarhus Institute of Advanced Studies COFUND Fellowship funded by the Aarhus University Research Foundation & the European Union’s Seventh Framework Programme, Marie-Curie Actions.

You can find the open-access article here.

Neuheimer Lab MSc Defense - Congrats Andreas!

Last month, lab member Andreas Mørch successfully defended his Biology MSc thesis entitled "Controls on interannual variation in Ammodytes dubius lipid content at Fyllas Banke & its implications for seabird predators". Congratulations Andreas on all your hard work! And a big thank you to thesis examiners Jane Behrens & Peter Grønkjær.

New lab member - Welcome Kris-Emil Mose Jørgensen!

This month, the Neuheimer Lab welcomes Kris-Emil Mose Jørgensen who joins us as a PhD Candidate to further the lab’s efforts exploring controls on early life history timing . Kris-Emil worked with The Danish Environmental Protection Agency (Miljøstyrelsen) after completing his MSc explaining growth rates in Atlantic cod (Gadus morhua) populations. Welcome Kris-Emil!

New Article: Match-mismatch dynamics in the Norwegian-Barents Sea system

Published this month in Marine Ecology Progress Series, we develop and apply a new match-mismatch metric to estimate the spatio-temporal overlap between Northeast Arctic cod and their prey in the Norwegian-Barents Sea. We show the new overlap metric can explain up to 29% of cod recruitment at age 3 years.

The study was led by Sofia Ferreira (Centre for Ecological and Evolutionary Synthesis, University of Oslo, Norway), and in collaboration with Joël Durant & Leif C. Stige (Centre for Ecological and Evolutionary Synthesis, University of Oslo, Norway), Bjarte Bogstad (Institute of Marine Research, Norway), and Natalia Yaragina & Irina Prokopchuk (Polar branch of Russian Federal Research Institute of Fisheries and Oceanography).

This work was funded by the European Union’s Horizon 2020 research and innovation programme through a Marie Skłodowska-Curie grant to Ferreira as well as the Research Council of Norway and an AIAS-COFUND Fellowship funded through the Aarhus University Research Foundation & the European Union’s Seventh Framework Programme, Marie-Curie Actions.

You can find the open-access article here.

Neuheimer Lab 2.0 - Aarhus University, Danmark

February 2020 marked our move to Aarhus University’s Department of Biology. I look forward to continuing our research and teaching efforts with the exciting group at AU’s Aquatic Biology.

Neuheimer Lab @ University of Oslo

Anna is in Oslo this week to meet with Sofia Ferreira and Joël Durant at the Centre for Ecological and Evolutionary Synthesis, University of Oslo. Under Sofia’s SPITFIRE project, we’re exploring match-mismatch effects for larval fish with implications for fisheries production. Anna will also present her work on the biological theory of relativity (more here).

New Article: Characterizing sources of mortality in fish early life stages

In a Fish and Fisheries publication earlier this year, we present a method of identifying sources of mortality for larval and juvenile fish from common survey observations (abundance and size).  We apply the method – a statistical state-space model – to identify vulnerable life stages (and important sources of mortality) for six economically and ecologically important fish populations.  Our results identify size-dependent survival and highlight habitat transitions (pelagic to demersal) as important mechanisms influencing fish recruitment. 

The work is a collaboration including those from the University of Oslo, National Oceanic and Atmospheric Administration, Polar Research Institute of Marine Fisheries and Oceanography, Institute of Marine Research, Oregon State University, University of Hawaii at Mānoa, and Aarhus University.  The collaboration arose from the NAMOR workshops organized by J. Durant with funds from the Research Council of Norway. An open-access pdf is available here.

Neuheimer Lab 2.0 - Moving to Aarhus University, Denmark

After 6 happy and productive years at UHM’s Department of Oceanography, the Neuheimer Lab will be moving to Aarhus University (AU) in Aarhus, Denmark beginning 01 February 2020. I am very excited to be joining the dynamic group in Aquatic Biology at AU’s Department of Bioscience. Student and postdoctoral opportunities associated with the move will be announced shortly.

I very much appreciate having had the opportunity to contribute our research and teaching efforts to the dynamic and supportive group in Oceanography at UHM (and the greater SOEST community). I look forward to continuing our collaborations moving forward.