Aquatic Food Web Ecology Lab, Dalhousie University

Research in the Aquatic Food Web Ecology Lab based at Dalhousie University in Halifax, Nova Scotia, Canada, focuses on the consequences of biodiversity loss to the functioning and stability of aquatic food webs. All of our work is done in a food web context, which means that its not just the numbers of species that we are interested in, but also the structure of the food webs in which those species are embedded. Most of our work is done in aquatic microcosms, small container ecosystems in which we can assemble food webs and then subject them to various types of disturbance regimes . We also use mathematical models to run "in silico" experiments, otherwise known as computer simulations, to study problems that are too complex or just not possible to conduct in natural systems.

Saturday, June 16, 2012

Murphy and Carscallen cleaning up!

Congratulations to Grace Murphy who was awarded an NSERC scholarship for her PhD research on the effects of anthropogenic disturbances on biodiversity and ecosystem functioning and to PhD student Mather Carscallen who won the InnovaCorp Clean Tech Open .

Lab at Bioball 2012

I was there in spirit (and on the placard) at ecologists rocking it out at the annual biology dinner/dance

Binary versus flow-based webs

Estimating trophic position in marine and estuarine food webs -- EcoSphere Binary approaches to assembling feeding links are often criticized as being less powerful and accurate than flow-based methods. Our results show a high concordance between binary and d15N estimates of trophic position as well as showing that in some cases binary estimates are better predictors of d15N than flow-based estimates, reaffirming the robustness of the structural approach to assembling food webs.

Polar food-webs

Do Arctic and Antarctic sea-ice food webs differ in structure and robustness to species loss? Find out in "Structure and robustness to species loss in Arctic and Antarctic ice-shelf meta-ecosystem webs" published online in Ecological Modeling.

Summer 2012

So much going on this summer. Mather Carscallen is heading out to Germany to work with Ulrich Brose and Amrei Binzer on the Allometric Trophic Model. Tamara Romanuk is giving a CSEE symposium talk at Evolution 2012 in Ottawa "Species Invasions in Complex Food Web Networks". We are also heading out to GlobalWeb II in Barcelona in July organized by Ross Thompson.

Wednesday, January 4, 2012


Melbourne life... one... link... at... a... time...
From left to right: front row: Ross Thompson; middle row: Neo Martinez, Tamara Romanuk, Jennifer Dunne, Bob Hall, Daniel Stouffer, Jason Tylianakis; back row: Roger Kitching, Ulrich Brose, Sally Hladyz, Heidi Rantala

A baby and the Cushman AWARD!

Jen Gaultier had her 2nd baby and won the Cushman Award which will be providing funds for helping us decipher food-web pathways in Atlantic go girl!

Honors Students 2011/2012

Trina Jolene "Response of placozoans to light"

Jess Hinch "Effects of increased temperature on salt marsh food-webs"

Alyssa Cirtwill "Latitudinal gradients in food-web structure"

Molly Whalen-Browne "Effect of increased temperature on the relation between diversity and stability in zooplankton"

Deja Gibson "Response predictability in ecosystem function following anthropogenic disturbances"

Charlotte Underwood "Food web structure of Atlantic salt-marshes"

Body Ecology

Marina Ritchie successfully defended her thesis titled "Structure and Function of the Human Microbiome"
Abstract: Humans harbour a diverse suite of microorganisms in and on their bodies. These microorganisms collectively amount to 10 times more cells than the cells in the human body, and their combined genomes have more than 100 times more genes than the human genome does. Despite our understanding of the composition, diversity, and abundance of microorganisms of the human body, it is surprising how little we know about the structure and function of the human microbiome. Here, I use network structure to describe interactions among human-associated microbiota and the human body by exploring differences in structure of human microbiomes across five regions of the body and the robustness of these networks to perturbations. My results show that positive interactions among microbiota are extremely important in structuring microbiome networks and those structural aspects of microbiome networks play a major role in their response to perturbations.

Wednesday, June 22, 2011

Come here big high trophic level fishy......

Romanuk, TN., A. Hayward, and J.A. Hutchings. 2010.
Trophic level scales positively with body size in fishes.
Global Ecology and Biogeography

New meta-analysis: diversity-stability relations

Experimental design and the outcome and interpretation of diversity–stability relations
Oikos, Volume 120, Issue 3, pages 399–408, March 2011 by Veronik Campbell, Grace Murphy,and Tamara N. Romanuk

The land of OZ

Tenure and promotion to Associate Professor (me!), Ph.D. status (Mather Carscallen) and a trip to Melbourne for GlobalWeb (organized by Dr. Ross Thompson) oh my!

Ecological Modelling Conference at Lake Garda

Network scientists sure know where to hold a conference. Just got back from 7th ECEM (European Conference on Ecological Modelling) which was held in Riva del Garda, Italy, from 30 May to 2 June 2011. Many thanks to Ferenc Jordan for organizing the conference and to Mike Fowler for the blog kudos on my talk (Devious topological strategies and stabilty in complex networks). The conference would not have been the same if Jurek Kolasa, Amrei Binzer, and Andrew Davies hadn't been there. Awesome science-schmooze.

Friday, September 3, 2010

...and they're off!

Connie Tuck "SCALING UP TO FOOD WEBS: EFFECTS OF TEMPERATURE ON STRUCTURE AND FUNCTION ALONG A LATITUDINAL GRADIENT" and Veronik Campbell "DYNAMICS OF SPECIES EXTINCTION AND RECOVERY IN MULTI-TROPHIC AQUATIC SYSTEMS" successfully defended their M.Sc. theses! Both received stellar reviews and though we are all sad to see them leave we are looking forward to see where they go.

Sunday, July 4, 2010

Sunday, June 13, 2010

ASLO/NABS in Santa Fe

Getting a bunch of limnologists and aquatic ecologists together in the desert? Yes please! In the photo (left to right): Neo Martinez, Tamara Romanuk, Richard Vogt, Lars Rudolph, Connie Tuck, Veronik Campbell on a well deserved afternoon off overlooking Santa Fe. Thanks ASLO?NABS and in particular to Alan Covich who organized our great interactive session
"Network Approaches to Understanding Complex Aquatic Ecosystem Dynamics"
Connie giving her first 'international presentation'.

Friday, May 7, 2010

Talks and kudos at the 2010 Lett Conference

Congrats are definitely in order for M.Sc. student Veronik Campbell who captured the best talk prize at the master's level at the 2010 Lett Symposium, a conference organized by graduate biology students at Dalhousie for her talk "Dynamics of populations on the edge of extinction".She, along with Constance Tuck, will also be presenting at the 2010 CSEE conference in Laval.Connie's talk "Robustness of Ecological Communities to Environmental Warming" also received very high praise and will also be presented at CSEE this year.

Wednesday, May 5, 2010


I don't know if we are more excited about eating Spätzle or learning to code the biodynamic model in C++ but either way we are very happy to be hosting Amrei Binzer, a visiting grad student from Uli Brose's lab in Germany this month. We are deep into species invasions simulations and thinking about lots of fun things like adding facilitation to the niche model. Thanks for loaning Amrei to us Uli!

Saturday, May 1, 2010

Interested in learning more about our research?

Want to science-schmooze with us this summer?
We are heading out to a number of conferences....

5th Annual CSEE meeting
May 9-12, 2010, Québec

Joint Meeting with ASLO & NABS
June 6-11, 2010, Santa Fe, New Mexico

Devious strategies and disturbance

How do ecological communities respond to increasing disturbance? A recent paper published by us in PlosOne suggests that as the severity of a disturbance increases, functional groups begin to respond differently.....although the importance of having high functional group diversity to maintaining stability is conserved across all levels of environmental stress.

Romanuk TN, Vogt RJ, Young A, Tuck C, Carscallen MW (2010) Maintenance of Positive Diversity-Stability Relations along a Gradient of Environmental Stress. PLoS ONE 5(4): e10378. doi:10.1371/journal.pone.0010378

Related papers:

Romanuk, T.N., R.J. Vogt, and J. Kolasa. 2009.
Ecological realism and mechanisms by which diversity begets stability.
Oikos 118:819-828.

Romanuk, T.N., B. Beisner, N.D. Martinez, and J. Kolasa. 2006.
Non-omnivorous generality promotes population stability.
Biology Letters 2:374-377.

Romanuk, T.N., R.J. Vogt, and J. Kolasa. 2006.
Eutrophication weakens the stabilizing effect of diversity on community and population variability.
Oikos 114:291-302.

Vogt, R., T.N. Romanuk, and J. Kolasa. 2006.
Species richness-variability relationships in multi-trophic aquatic microcosms.
Oikos 113:55-66.

Romanuk, T.N., and J. Kolasa. 2004.
Population variability is lower in diverse rock pools when the obscuring effects of local processes are removed.
Ecoscience 11:455-462.

Romanuk, T.N., and J. Kolasa. 2002.
Environmental variability alters the relationship between species richness and community variability in natural rock pool microcosms.
Ecoscience 9:55-62.

Tuesday, April 20, 2010

Rocking it out at BioBall 2010

Veronik, Marina, Catherine, Connie and I rocking it out at BioBall 2010....

Thursday, April 8, 2010

New MSC student: Grace Lotz

She's been managing our lives (and our lab) for a while now and has been hanging around the lab even longer (I was Grace's departmental advisor for her honors thesis on the feeding ecology of grey whales back in 08/09) - this coming September she joins us as a MSc student. Welcome Grace!

baby salmon need trees!

Next time you are driving the "Sea to Sky" highway up to Whistler take a moment to think of the salmon fry and the foreshore development. Chum salmon fry NEED trees!

Romanuk, T.N. and C.D. Levings. 2010.
"Reciprocal Subsidies and Food Web Pathways Leading to Chum Salmon Fry in a Temperate Marine-Terrestrial Ecotone". PlosOne.

Also check out: Romanuk, T.N. and C.D. Levings. 2006. Relationships between fish and supralittoral vegetation in nearshore marine habitats. Aquatic Conservation: Marine and Freshwater Ecosystems 16:115-132.

Romanuk, T.N., and C.D. Levings. 2005. Stable isotope analysis of trophic position and terrestrial vs marine carbon sources for juvenile Pacific salmonids in nearshore marine habitats. Fisheries Management and Ecology 12:113-121.

Romanuk, T.N., and C.D. Levings. 2003. Associations between arthropods and supralittoral vegetation: dependence of terrestrial and aquatic taxa on vegetation. Environmental Entomology 32:1343-1353.

Friday, March 19, 2010

Joined the PlosOne editorial team as an academic editor!

I am a big fan of open access publishing and in particular, the Plos journals. To support the trend I have just joined the PlosOne team as an Academic Editor!

Friday, March 12, 2010


Just got back from a conference in Sendai, Japan: "Ecosystem Management Applying to Ecosystem Adaptability Science: Robustness and stability of organisims and ecosystems". This conference was just incredible - 25 speakers, 5 days, great science, and good friends! Here is a shot of Kevin McCann and I taking a nature walk on one of our afternoons off. I would like to thank Hiroko and all the conference organizers for inviting me. One of the best conferences I can remember! (The other dude is Macaca fuscata - a trip to Japan is nothing without a side-trip to see the snow monkeys!

Thursday, February 18, 2010

Honors students at the Cameron Conference

Kristen Vandenburg, Karla Armsworthy, Jennifer Malcolm, Vanessa Brisson, and Cashelle Farley presenting their research at the annual Cameron Conference for honors students.

Monday, January 11, 2010

Mediterranean Is Scary Laboratory of Ocean Futures

Press In Wired Science

“It’s difficult to know exactly what’s going to happen elsewhere, but the principles can be extrapolated,” said Marta Call, a Dalhousie University marine biologist who has modeled the interactions of Mediterranean species. In a paper published last year in Ecosystems, she and her colleagues described Mediterranean food webs as “in an advanced state of degradation.”

Read More

“Structural Degradation in Mediterranean Sea Food Webs: Testing Ecological Hypotheses Using Stochastic and Mass-Balance Modelling.” By Marta Coll, Heike K. Lotze, and Tamara N. Romanuk. Ecosystems, Vol. 11 No. 6, Sept. 2008.

Tuesday, January 5, 2010

Mather Carscallen Joins the FWL

Mather Carscallen has been working with us for nearly three years now and this January formally joins us as an M.Sc student. He is working on polar food webs and the potential consequences of climate change on food web structure in the Arctic and Antarctic. Welcome Mather!

Thursday, December 17, 2009

What to do when you get invited to give a talk?

Take the lab on a road trip of course. Tamara, Connie, Veronik, Catherine, and Marina celebrating the end of a term in New Brunswick.

Kayla Hamelin at the USRA poster session

"The Tangled Web: Who eats whom in the Nova Scotia rock pools" - by far the coolest poster at the session:)