Research
Past projects
I worked mainly on questions regarding environmental effects on behavior and ecology using perch (Perca fluviatilis), Atlantic salmon (Salmo salar), brown trout (Salmo trutta), genetically modified coho salmon (Oncorhynchus kisutch) and a stick insect (Peruphasma schultei). Within this work, I was interested in the relative contributions and interactions between genetics and the environment in shaping phenotypes with a special focus on temperature. Funding for this work came from the Swedish Research Council Vetenskapsrådet. I pursued several other research areas in collaboration with numerous Principal Investigators (PI) who then provided the main funding for that work. (All photos are from experimental animals).
Long-term acclimatization to elevated temperature in perch
This is a project using a large enclosure in the Baltic sea receiving warmed water from the nuclear power plant at Forsmark since 1980. Our questions concern effects of these warmed conditions on the behavior and ecology of perch and how an increased temperature influence the interactions of perch with the surroundings. In collaboration with researchers at Göteborg University, Sweden and University of Southern Pacific, Fiji, we link these effects to physiological alterations presumably caused by the temperature increase. More information is available from the Megawatt Thermal Biology Lab website.
Collaborators: Dr Erik Sandblom, Dr Fredrik Jutfelt, Dr Susanna Piovano
Representative publications:
Rowinski, P.K., Mateos-Gonzalez, F. Sandblom, E., Jutfelt, F., Ekström, A., & Sundström, L.F. 2015. Warming alters body shape in European perch Perca fluviatilis. Journal of Fish Biology 87: 1234-1247.doi: 10.1111/jfb.12785
Perch (Perca fluviatilis)
Host-parasite co-evolution
We use the heated system in the Biotest enclosure to study the co-evolution between hosts and parasites. Our hosts are perch and the parasite is Diplostomum. In short, the parasite lives in snails, leave the snail to infect the perch where it migrates from the gills to the eye. This presumably affects the perch making it more exposed to bird predation, and the birds are the final host of the perch. We are interested in the possible co-evolution between the fish and parasite that may have occurred during the 30+ years of warming in the Biotest enclosure.
Collaborator: Dr Mats Björklund (PI), Dr Fernando Mateos
Representative publication:
Mateos-Gonzalez, F., Sundström, L.F., Schmid, M. & Björklund, M. 2015. Rapid evolution of parasite resistance: Insights from a large scale field experiment. PLoS One 10:e0128860. doi: 10.1371/journal.pone.0128860
Diplostomum parasite (left) coming from a perch eye (right).
Compensatory growth
In this project I am interested in learning more about compensatory growth - a period of rapid growth following a period of imposed slow growth, typically through food restriction or low temperature. Work is typically carried out by monitoring the animals' growth for a period, then subjecting one group to starvation and the other to continued feeding. After one or a few weeks, depending on fish size, all fish are then fed again. The group that was starved is now expected to eat more food and within weeks catch up in size with those animals fed throughout the experiment.
However, several studies suggests that this growth compensation, or the starvation period, involve costs for the animal such as reduced locomotory capacity or reproductive output later in life, in addition to increased predation risk during the compensatory phase. I therefore examine also potential costs of the starvation-compensation treatment.
Compensatory growth and behavior of Peruphasma schultei
I have recently started working on a very charming species of stick insect from Peru, described as recent as in 2007. It grows relatively large (about 7 cm) and is easy to keep in captivity. I am intersted to see whether it exhibits compensatory growth and if so potential effects on reproductive output in females. Along the compensation I am also interested to see whether behaviors are altered during the compensatory phase.
Peruphasma schultei
Collaborator: Dr Mare Lõhmus
Environmental regulation of compensatory growth
Much of the work carried on compensatory growth has been done in the laboratory where it is relatively easy to control food intake of fish and keep them in large number with high probability of recapture. However, the evolutionary and ecological significance of growth compensation can only be fully understood of these laboratory studies are combined with work in nature. An important aspect that we are studying in brown trout in small streams along the Swedish west coast is what environmental factors limit compensatory growth under natural conditions. This work is labor intensive during a few days at a time and involves electro-fishing to capture fish.
Collaborators: Dr Jörgen Johnsson, Dr Rasmus Kaspersson, PhD-student Joacim Näslund
Representative publications:
Sundström, L.F., Kaspersson, R., Näslund, J. & Johnsson, J.I. 2013. Density-dependent compensatory growth in brown trout (Salmo trutta) in nature. PLoS One 8:e63287. doi:10.1371/journal.pone.0063287
Phenotypic plasticity
Atlantic salmon
Development in fish is very flexible and Atlantic salmon are among the most flexible among the fishes, in how environmental conditions influence their development. This response to the environment can be adaptive if it increases the fitness of the individual, but also maladaptive if the development triggered by the environment reduces fitness. For example, running water may produce more streamlines bodies, which may be good in environment with high water velocities but not in environments where water is not moving much. I am particulalry interested in understanding how the organism detects environmental factors and how this is translated into phenotypic responses. Further, I am looking into during which time period an individual is responsive to specific conditions and and for long this response can occur and if it can be reversed by changing conditions.
Atlantic salmon (Salmo salar)
Echinopora coral
Corals are important structure-building animals around the world, but they are also facing challenges mainly due to anthropogenic reasons such as global warming and destructive fishing methods. Changes in weather may also influence water movements which in turn may influence coral growth. In this project we aim to look at the growth of Echinopora sp. coral in response to different water currents. We expose corals to laminar flow, wave motion and shifting laminar flow. This work is being done at Aquaria in Stockholm.
Collaborators: Piotr Rowinski
Mother colony of Echinopora sp. at Aquaria and one of the frags used in the experiment
Providing baseline data for ecological risk-assessment of genetically modified fish
The advent of genetically modified (GM) animals has created concern over potential ecological risks that could be associated with these animals should they be released or escape into the natural environment. This is particularly of concern when it comes to fish because the GM fish are often close to the wild-type fish and may therefore be more likely to survive in nature than for example the GM goat (e.g. ATryn) or pig (Enviropig). In addition, fish live in water which make it even more cumbersome, and often impossible, to retrieve escaped specimens to a 100%. An important work has therefore been to assess the risks associated with rearing GM fish at a commercial scale. I am also involved in the development of guidelines for the European Union in the risk-assessment of genetically modified animals to be placed on the EU market by serving as an expert on the working panel of GM fish at the European Food Safety Authority (EFSA).
Coho salmon and rainbow trout
The work on coho salmon and rainbow trout has involved simulating natural conditions as an attempt to examine how GM fish growth and survive under various conditions relevant for nature. This work has been carried out within a confined laboratory in collaboration with Dr Bob Devlin at the Centre for Aquaculture and Environmental Research in West Vancouver, Canada. Dr Devlin developed several GM salmon and most of my work was carried out on coho salmon which is the strain best characterized. Both these coho salmon and the rainbow trout a promotor sequence attached to a growth hormone gene inserted into their genome which allows them to grow 1-2 times faster than unmodified wild-type fish.
Part of this project involves examining genetic and environmental effects on the development of the fish brain. This is in collaboration with Dr Niclas Kolm and Alexander Kotrschal at Uppsala University.
Another part involves examining the hormonal regulation of appetite in transgenic fish and this work is in collaboration with Dr Mare Lõhmus.
Collaborators: Dr Bob Devlin (PI), Dr Mare Lõhmus, Dr Wendy Vandersteen, Dr Glenn Crossin
Representative publications:
Devlin, R.D., Sundström, L.F., & Leggatt, R.A. 2015. Potential ecological and evolutionary consequences of growth-accelerated genetically engineered fishes. BioScience 65: 685-700. doi: 10.1093/biosci/biv068
Sundström, L.F. & Devlin, R.H. 2011. Increased intrinsic growth rate is advantageous even under ecologically stressful conditions in coho salmon (Oncorhynchus kisutch). Evolutionary Ecology 25: 447-460. doi: 10.1007/s10682-010-9406-1
Sundström, L.F., Lõhmus, M. & Devlin, R.H. 2010. Migration and growth potential of coho salmon smolts: implications for ecological impacts from growth-enhanced fish. Ecological Applications 20: 1372-1383. doi: 10.1890/09-0631
Sundström, L.F., Tymchuk, W.E., Lõhmus, M. & Devlin, R.H. 2009. Sustained predation effects of hatchery-reared growth hormone transgenic coho salmon Oncorhynchus kisutch in semi-natural environments. Journal of Applied Ecology 46: 762-769. Doi: 10.1111/j.1365-2664.2009.01668.x
Lõhmus, M., Raven, P. A., Sundström, L.F. & Devlin, R.H. 2008. Disruption of seasonality in growth hormone-transgenic coho salmon (Oncorhynchus kisutch) and the role of cholecystokinin in seasonal feeding behavior. Hormones & Behavior 54: 506-513. doi: 10.1016/j.yhbeh.2008.02.010
Sundström, L.F., Lõhmus, M., Tymchuk, W E & Devlin, R.H. 2007. Gene-environment interactions influence ecological consequences of transgenic animals. Proceedings of the National Academy of Sciences of the USA 104: 3889-3894. doi: 10.1073/pnas.0608767104
Coho salmon fry (Oncorhynchus kisutch)
Common carp
Common carp is a species also modified for rapid growth by the same means as the coho salmon and rainbow trout, that is a gene inserted for over-production of growth hormone. While salmon and trout are carnivorous, the carp is more of an omnivore thereby presenting a variety on the theme which means it can provide additional important information that the salmonid species cannot.
Collaborators: Dr Zoyan Zhu (PI), Dr Tangling Zhang (PI), Dr Ming Duan
Representative publications:
Duan, M., Zhang, T., Hu, W., Li, Z., Sundström, L.F., Zhu, T., Zhong, C., & Zhu, Z. 2011. Behavioral alterations in GH transgenic common carp may explain enhanced competitive feeding ability. Aquaculture 317: 175-181. doi: 10.1016/j.aquaculture.2011.04.013
Duan, M., Zhang, T., Hu, W., Sundström, L.F., Wang, Y., Li, Z. & Zhu, Z. 2009. Elevated ability to compete for limited food resources by ‘all fish’ growth hormone transgenic common carp (Cyprinus carpio L.). Journal of Fish Biology 75: 1459-1472. doi:10.1111/j.1095-8649.2009.02393.x
Behavioral assessment of a laboratory model species - zebra fish
Model species in biology play a crucial role in research, such as mice in medical research and fruit flies in genetic research. An upcoming model species is the zebra fish (Danio rerio) that is gaining more and more interest from biological researchers. In this project I am interested in knowing more about how different behavioral traits are correlated in the zebra fish as behavioral data are often collected as part of the treatment on studies.
Collaborators: Dr Svante Winberg (PI), Josefin Dahlbom (PhD-student)
Representative publications:
Dahlbom, S.J., Lagman, D., Lundstedt-Enkel, K., Sundström, L.F. & Winberg, S. 2011. Boldness predicts social status in zebrafish (Danio rerio). PLoS One, 6:e23565. doi:10.1371/journal.pone.0023565
Hormonal regulation of appetite in birds
Feeding behavior and growth regulation are important aspects in the life of any animal. In this project I examined the role of various hormones, mainly leptin, on feeding behavior and growth in birds. This work was used for the PhD thesis of Mare Lõhmus.
Collaborators: Dr Mare Lõhmus (PI)
Representative publications:
Lõhmus, M., Sundström, L.F. & Moore, F.R. 2006. Non-invasive corticosterone treatment changes foraging intensity in red-eyed vireos (Vireo olivaceus). Journal of Avian Biology 37: 523-526. doi: 10.1111/j.0908-8857.2006.03733.x
Lõhmus, M., Sundström, L.F. & Silverin, B. 2006. Chronic administration of leptin in Asian blue quail. Journal of Experimental Zoology 305A: 13-22. doi: 10.1002/jez.a.240
Lõhmus, M. & Sundström, L.F. 2004. Leptin and social environment influence the risk taking and feeding behaviour of Asian blue quail. Animal Behaviour 68: 607-612. doi: 10.1016/j.anbehav.2003.12.019
Lõhmus, M., Sundström, L.F. El Halawani, M. & Silverin, B. 2003. Leptin depresses food intake in great tits (Parus major). General and Comparative Endocrinology. 131: 57-61. doi: 10.1016/S0016-6480(02)00643-3
Effects of hatchery-rearing on phenotypic development in brown trout (Salmo trutta)
Many fish species are reared under hatchery conditions for later release to the natural environment to support wild populations of that species. However, due to the plastic development in fish, those reared in the hatchery are not always well adapted to a life in nature. In this project I examine effects of hatchery rearing on behavior of brown trout, and subsequent performance in nature. This work was used for my PhD thesis.
Collaborators: Dr Jörgen Johnsson (PI), Dr Torgny Bohlin, Dr Johan Höjesjö
Representative publications:
Sundström, L.F., Petersson, E., Johnsson, J.I., Höjesjö, J. & Järvi, T. 2004. Hatchery selection for increased boldness in brown trout fry: implications for dominance. Behavioral Ecology 15: 192-198. http://beheco.oxfordjournals.org/cgi/content/full/15/2/192
Sundström, L.F. Lõhmus, M. & Johnsson, J.I. 2003. Investment in territorial defence depends on rearing environment in brown trout (Salmo trutta). Behavioural Ecology and Sociobiology 54: 249-255. doi: 10.1007/s00265-003-0622-3
Bohlin, T., Sundström, L.F., Johnsson, J.I., Höjesjö, J. & Pettersson, J. 2002. Density-dependent growth in brown trout: effects of introducing wild and hatchery fish. Journal of Animal Ecology 71: 683-692. doi: 10.1046/j.1365-2656.2002.00631.x
Sundström, L.F. & Johnsson, J.I. 2001. Experience and social environment influence the ability of young brown trout to forage on live novel prey. Animal Behaviour 61: 249-255. doi: 10.1006/anbe.2000.1593
Behavior and ecology of lemon sharks
Many shark species are threatened from over-fishing and habitat destruction. The lemon shark is no exception and its habitats in the important nursing area around Bimini Islands, Bahamas are being developed into casino and golf courses. In this project I look at movement and swimming behavior of subadult lemon sharks (Negaprion brevirostris) fitted with speed-sensing transmitters to better understand when, how and why sharks are being active. This work was used for my MSc thesis.
Collaborators: Dr Sonny Gruber (PI) at the Bimini Biological Field Station
Representative publications:
Sundström, L.F., Gruber, S.H., Cleremont, S.M., Correia, J. P. S., de Marignac, J.R.C., Morrissey, J.F., Lowrance, C. R., Thomassen, L. & Oliveira, M. T. 2001. Review of elasmobranch behavioral studies using ultrasonic telemetry with special reference to the lemon shark, Negaprion brevirostris, around Bimini Islands, Bahamas. Environmental Biology of Fishes60 (1-3): 225-250. doi: 10.1023/A:1007657505099
Sundström, L.F. & Gruber, S.H. 1998. Using speed-sensing transmitters to construct a bioenergetics model for subadult lemon sharks, Negaprion brevirostris (Poey), in the field. Hydrobiologia 371/372:241-247. doi: 10.1023/A:1017031406947