Master thesis 30/60 ECTS

Last changed: 10 June 2024
Herring

Do you want to work with marine biology, marine ecology, freshwater biology, freshwater ecology, limnology or sustainable development? Make a difference for the Baltic Sea, the Skagerrak or Kattegat, for lakes or running waters! As a master thesis worker at our department, you will get the chance to deal with real problems in ongoing research projects, and have supervisors who are Sweden's leading experts in the field. You get to use theoretical knowledge in practice, and get the chance to participate in exciting fieldwork.

Our current calls concern a variety of topics in our field, such as fish, fisheries, shellfish, seals, waterfowl, ecosystems and sustainability issues. 

Current calls for master thesis 30/60 ECTS

(Are you looking for a bachelor thesis project (15 ECTS), go and have a look here!)

Energy Flow Efficiency in Marine Ecosystems under Climate Change

Master Project in Biology (30 - 60 credits).
Starting late summer 2024.

Aim

Explore how warming alters the efficiency of energy transfer from plankton to fish in pelagic and benthic coastal food webs. This MSc thesis project is part of a larger project focused on maintaining ecosystem services amid environmental stressors under climate change, key to ensure aquatic ecosystems continue to act as carbon sinks and support fish biomass production.

Background

Global warming is intensified in coastal regions of the Baltic Sea, affecting food webs with both pelagic (mid-water) and benthic (seafloor) pathways. Previous studies have overlooked benthic  pathways, and the combined role of warming and increased nutrient inputs which boost pelagic, but not benthic, production.

Methods

Conduct an experiment in outdoor tanks in place at our field site in Forsmark, working with phytoplankton, zooplankton, and fish. You will manipulate temperature and habitat availability. Specific  details will be developed by the student with guidance from expert supervisors.

Skills you will gain

  • Experimental design and execution
  • Plankton and fish sampling techniques
  • Aquatic organism identification
  • Advanced statistical analysis
  • Scientific writing and communication

You will also become a member of our "Fish in Food-Webs" research group! You will be invited to participate in group meetings and seminars at Campus Ultuna in Uppsala.

Contact

benjamin.mooney@slu.se or magnus.huss@slu.se

Fish welfare: Physiological responses to anaesthisia in brown trout

Bachelor project (15 ECTS) or Master project (30/60 ECTS) in biology

Fish welfare: Physiological responses to anaesthisia in brown trout

This research project aims to explore how brown trout respond to different anaesthetics. When set in water with an anaesthetic agent, fishes initially respond with increased activity. This results in  a cascade of physiological processes in the fish. In this project some of these responses will be investigated.

Background

There is a wide array of different teleost species used in scientific research world-wide. These fish are frequently anaesthetised for various procedures and previous studies suggest that there is a divergence in the response to different anaesthetics among species. The use and efficiency, from a practical point of view, of anaesthetics in different species have been studied and reviewed. However, the fish welfare aspect and the in depth understanding of the pharmacological mechanism of action and effect in different species are largely unknown. In view of our increased awareness of animal welfare, also regarding fish, along with an increased use of fish as experimental animals, standardised anaesthetic protocols that are species specific is a necessity to assure best practices with focus on fish welfare.

In earlier experiments we have shown that the stress (cortisol) response in brown trout appear to be higher in more acid water; non-buffered tricaine methanesulfonate lower the pH.

Methods

This project we will attempt to investigate thes further by comparing the response of juvenile brown trout to four treatment (non-buffered tricaine methanesulfonate, buffered tricaine methanesulfonate., river water and river water with pH=3 (using hydrochlorid acid).

Blood sample will be taken from about 80 trout and the blood will late be analyzed.

Depending on the number of credits the student wish to achieve the brains of the trout will also be sampled and analyzed for monamines (such as dopamine and noradrenaline).

Contacts

Erik  Petersson
Department of Aquatic Resources (SLU Aqua)
erik.h.petersson@slu.se 010-4784239

Svante Winberg
Uppsala University
svante.winberg@neuro.uu.se
Swedish University of Agricultural Sciences, Department of Anatomy, Physiology and Biochemistry
Svante.winberg@slu.se

Fish welfare: Physiological responses to anaesthisia in zebrafish

Bachelor level (15 ECTS) or Master level (30/60 ECTS) in biology 

Fish welfare: Physiological responses to anaesthesia in zebrafish

This research project aims to explore how zebrafish respond to different anaesthetics. When set in water with an anaesthetic agent, fishes initially respond with increased activity. This, in turn, onset a cascade of physiological processes in the fish. In this project some of these responses will be investigated.

Background

There is a wide array of different teleost species used in scientific research world-wide. These fish are frequently anaesthetised for various procedures and previous studies suggest that there is a divergence in the response to different anaesthetics among species. The use and efficiency, from a practical point of view, of anaesthetics in different species have been studied and reviewed. However, the fish welfare aspect and the in depth understanding of the pharmacological mechanism of action and effect in different species are largely unknown. In view of our increased awareness of animal welfare, also regarding fish, along with an increased use of fish as experimental animals, standardised anaesthetic protocols that are species specific is a necessity to assure best practices with focus on fish welfare.

Zebrafish is the second most common laboratory aninmal in Sweden right now and knowledge about zebrafish behavior and physiology are important for future care and housing of the species.

In earlier experiments we have gathered information about the stress response in zebrafish to metomidate and tricaine methanesulfonate. We now like to investigate the response to three other  anaesthetic methods: eugenol, benzocaine and rapid cooling.

Methods

Zebrafish will be anaesthetized with the three methods mentioned above, the fish will thereafter be sampled for cortisol (whole –body). This require that the cortisol is extracted, i.e. you will spend many days in the laboratory.

Depending on the number of credits the student wish to achieve the brains of the zebrafish will also be sampled and analyzed for monamines (such as dopamine and noradrenaline).

Contact

Erik  Petersson
Department of Aquatic Resources (SLU Aqua)
erik.h.petersson@slu.se 010-4784239

Svante Winberg
Uppsala University
svante.winberg@neuro.uu.se
Swedish University of Agricultural Sciences, Department of Anatomy, Physiology and Biochemistry
Svante.winberg@slu.se

Ecology and management of the European eel

Bachelor projects in biology (15 ECTS)

Ecology and management of the European eel, several projects available!

Background

The European eel, Anguilla anguilla, is red listed as critically endangered due to a steep population decline. Current management efforts aim to reverse this negative development. There are many knowledge gaps regarding everything from ecology, behaviour, and physiology to development of stock assessment parameters. You can help us fill these knowledge gaps!

We have a great variety of bachelor degree projects and research training/internship related to evaluating and synthesizing information about ecology, management and data collection of the European eel. There are also opportunities to assist in lab work and field activities, such as tagging, fyke-net fishing, dissections, and more (although keep in mind that this can
be difficult to fit within a 15 hp project!).

Project examples

  • Evaluating tagging and tracking data of eels in river systems, lakes and in the sea. Students can be involved in the tagging and tracking procedures, depending on time availability. Topics that can be addressed include survival (fisheries induced survival, hydropower induced mortality), movement, long distance migration, etc.
  • Improve data collection programs. To monitor the eel stock, data is collected on a number of variables, such as landings, individual length, parasite prevalence, age, etc. Since data collection is time consuming and costly it is important that it is efficient. Any improvements that can be made to the monitoring programs are highly valuable, including 3R aspects.
  • Evaluation of management activities such as restocking and fisheries regulations.
  • Behavioural and physiological studies.

The work will be supervised by Dr Josefin Sundin and Dr Philip Jacobson. Depending on the project, the student should have an interest in fish ecology, behavioural ecology, fisheries science, data analysis, statistics, and scientific writing.

Location

At the Swedish University of Agricultural Sciences (SLU Aqua) in Drottningholm (Stockholm), Uppsala-Ultuna, or Öregrund. Several projects can also be done online.

Josefin Sundin, Researcher
Department of Aquatic Resources, Institute of Freshwater Research, SLU
josefin.sundin@slu.se, +46 10 478 42 24

Fish ecology and fisheries in Tanzania

Master 60 ECTS

Are you interested in fish, fish ecology and fisheries and would like to do a Masters project in Tanzania?

Our research group is looking for a Masters student to conduct their Master thesis work (suggested 60 ECTS) within our project “FishLinks - Scrutinizing the impact of tourism-driven fish consumption on reef fish communities: a socio-environmental study in tropical seascapes”. The project starts early 2024 with fieldwork planned from August–October in Tanzania.

The focus of the Master project is related to the question of how tourism-driven fishing effects the fish communities on shallow- and deep- coral reefs in Tanzania. Suggested fieldwork sites being Zanzibar (high tourism) and Mafia Island (low tourism). Data collection will mainly be done by deploying baited remote underwater videos (BRUVs) by boat. There are also opportunities within the Masters project to develop methods or research question further. If you think this sounds like an exciting project, do not hesitate to contact:

Maria Eggertsen, Researcher
Department of Aquatic Resources, Institute of Coastal Research, SLU
maria.eggertsen@slu.se, +46 10 478 41 41

Charlotte Berkström, Researcher
Department of Aquatic Resources, Institute of Coastal Research, SLU
charlotte.berkstrom@slu.se, +46 10 478 41 65

Diana Hammar Perry, Environmental Monitoring and Assessment Analyst
Department of Aquatic Resources,  SLU
diana.perry@slu.se, +46(0)10-478 40 97

Seals and cormorants

Seals and cormorants - Top predators in Swedish waters

Suggestions of degree projects

The suggested topics are suitable for master student projects. The projects can include field work, lab work, literature studies, data analysis and scientific writing.

The contents and scope of the work can be discussed and adapted to prevailing conditions.

Background

The populations of seals and cormorants in Sweden have increased in size and distribution during the last decades.

Consequently, requirements and needs of information about the ecological roles of seals and cormorants have increased, e.g. for inclusion of top predators in ecological models and for development of ecosystem-based management. In addition, conflicts with fish conservation biology and coastal fisheries have intensified.

At present, relevant information on prey choice and abundance of these predators and their impact on fish stocks is insufficient.

Diet analysis of seals and cormorants

  • Diet variability
  • Methodology (DNA, image analysis)

Monitoring of seals and cormorants

  • Photo-ID
  • Camera surveillance
  • Regional monitoring, e.g. in marine protected areas
  • Abundance estimates

Predator-prey dynamics

  • Prey selectivity
  • Correlations between diet data and fish monitoring data

Contact

Karl Lundström, Researcher
Department of Aquatic Resources, Institute of Marine Research, SLU
karl.lundstrom@slu.se, +46 10 478 41 38

Developing a socio-ecological model for risk assessment in the Baltic Sea

Bachelor's level (15 ECTS) or Master's level (30 ECTS)

Developing a socio-ecological model for risk assessment in the Baltic Sea

Thesis work in biology or sustainable development at the Department of Aquatic Resources, Swedish University of Agricultural Sciences

Within this project you will have the opportunity to develop a socio-ecological model for the Bothnian Sea that can be used for future management decisions in collaboration with stakeholders, managers and scientists.

Background

A key aim in ecosystem-based management (EBM) is to establish common goals among stakeholders, as this is expected to enable the continued delivery of ecosystem services, while reducing user conflicts. Socio-ecological models are often used to support this aim. The models help increase the understanding between stakeholders and scientists and investigate how management actions could affect the ecosystem and the people who depend upon it. The Swedish Agency for Marine and Water Management has initiated an EBM pilot project in the southern Bothnian Sea to involve stakeholders in developing an ecosystem-based management that integrates environmental goals with societal goals for the region.

Project

As part of the pilot EBM project, you will develop a socio-ecological model for the Bothnian sea in collaboration with stakeholders, managers and scientists. This, so called fuzzy cognitive model can be used in preparing future management decisions and increase the understanding between managers, stakeholders and scientists of the ecological and societal processes that affect environment status.

Practical work includes conducting interviews with managers and stakeholders and contributing to workshops within the southern Bothnian Sea EBM project. You should be familiar with R, interested in ecosystem-based management and comfortable interacting with people of different backgrounds. No previous modelling experience is necessary.

Contact

Carolyn Faithfull, researcher
Department of Aquatic Resources, Institute ov Coastal Research , SLU
carolyn.faithfull@slu.se, +46(0)10-478 41 74

Round goby – turning risk to resource

Bachelor's level (15 ECTS) or Master's level (30/60 ECTS)

Round goby – turning risk to resource

Thesis work in biology or environmental science at the Department of Aquatic Resources, Swedish University of Agricultural Sciences

The round goby is native in the Black sea and Capian Sea but has probably come by ballast water to the Baltic Sea. It was first reported 1990 in the bay of Gdansk where ot is now the most common coastal fish species. In 2008 it was reported in Sweden for the first time, in the archipelago of Karlskrona. It now occurs from Kalmar Sound up to Gävle and also around Gotland and in Gothenburg.

The round goby is an invasive species with high reproduction speed and highly tolerant for environmental stressors. There is a risk that it will compete with other bottom dwelling species and also consume eggs & fry of native species but it can also be a resource for predatory fish and humans. One concern is that it may invade freshwater systems and knowledge about its migrating capability and potential barriers to stop it from entering rivers is needed. In order to utilize the species and develop efficient fishing gear knowledge is needed about the behavior of the fish around different fishing gears. The suggested projects below are experimental studies contributing with knowledge in both these important areas and they are part of the Research project Round goby – turning risk to resource.
All experiments are conducted in Älvkarleby, by the river Dalälven south of Gävle, either at SLU Fisheries Resaerch Station (FFS) or at the Vattenfalls experimental facility Laxeratorn. Depending on your skills and interest the thesis can either be within biology or environmental science with room for personal research questions. The work is flexibel and can be either on candidate or master level.

  1. Migration ability (15-60 ETCS), ), practical work is done during 3-6 weeks between August to September in Vattenfall Laxeratorn with potential complementing studies at FFS in October for the 60hp work. In this experiment the ability to migrate in an artificial fisheway at different speed of the water and with different barriers is studied for round goby, trout and bullhead. The study can be done on one or several species depending on the number of credits of the thesis. The work can also be done later in the year on recorded videomaterial from the experiments.

  2. Behaviour around fishing gear (15-60 ETCS), practical work is done during 2-3 weeks in September in the Laxelerator. In this experiment the behehaviour of round goby in the vicinity of a fishging gear is studied with the objective to create efficient methods to catch round goby. The work can also be done later in the year on recorded videomaterial from the experiments.

Contact

Ann-Britt Florin, Head of Division
Department of Aquatic Resources, Institute of Coastal Research, SLU
ann-britt.florin@slu.se, +46 10 478 41 22

Round goby – turning risk into resource

Thesis projects about salmonids in river Dalälven

Bachelor (15 ECTS) or Master level (30/60 ECTS)

Thesis projects about salmonids in river Dalälven

SLU:s Fisheries research station in Älvkarleby produce around 140 000 salmon and trout per year for river Dalälven. A prerequisite for environmental friendly and ethical aquaculture is that reserach is conducted on breeding and rearing of fish. Here we have ongoing reserach and environmental analsysis, and we have aquarieas, creeks and streams for experiments and in addition skilled personel.

We are looking for students for the following projects:

  1. Survival of salmon and trout smolt. The cormorant has been identified as a potentially important predator on smolt (salmonid juveniles) but scientific estimates from todays situation in river Dalälven is missing. Since some of the smolt is tagged with pit‐tags it is possible to look for these tags in cormorant colonies. The project involves scanning after pit‐tags in cormorant colonies along the coast but may also include investigations of regurgitates from cormorants or other fisheating birds. The field part is conducted after the breeding season of the birds, i.e. sep‐nov 2020

  2. Enhanced quality of stocked fish. It is desirable that the stocked fish similar to wild fish, but a common problem is that reared fish have damaged finns and also grows to fast and becomes to fat compared to wild fish. In this project the effect of different feedingregimes on condition, survival and fin damage is investigated. Also experiments with different densities of fish can be included. The project can take place almost anytime between march and december.

  3. Historic trends of spawning fish in river Dalälven. Breeding and rearing has taken place at the fisheries resaerch station for amlost 100 years. During this time data on the wild fish migrating from the sea has been collected which makes it possible to study changes in salmon and trout populations in the river in for example size, condition eggsize etc. This project can either be fully theoretical and take place anytime during the year or involve some practical work during either the fishing (aug) or breeding (oct) season.

Depending on previous education and interest the thesis can either be in ecology or environmental analysis and there is room for reserach questions of your own making. The extent is flexibel and the thesis can be done either on candidate or master level.

Contact

Ann-Britt Florin, Head of Division
Department of Aquatic Resources, Institute of Coastal Research, SLU
ann-britt.florin@slu.se, +46 10 478 41 22

Cost-effective sampling of Baltic cod for multispecies modelling

Master project in Ecology (30-60 credits)

Study on cost-effective sampling of Baltic cod stomachs for the purpose of multispecies modelling

The paradigm shift from single species to ecosystem based fisheries management (EBFM) requires a broader, mechanistic and more in-depth understanding of marine ecosystems. Multispecies models able to account for trophic interactions and the effect of environmental variability on populations are an essential tool to move towards an EBFM. To account for predator-prey interactions in age-size structured population dynamic models high quality information on predator consumption, prey preference and trophodynamics are essential. Stomach data provide fundamental information on predators’ diet, but their collection has been generally limited which is considered one of the limiting factors for the implementation of multispecies models for the purposes of fisheries advice within the context of EBFM.

The Baltic Sea has been one of the fortunate exceptions. Here, stomachs of cod, the main predatory fish in the system, have been collected for decades. This dataset is important not only for the implementation of advanced multispecies models for EBFM in the Baltic, but also because it can serve as a benchmark to design future stomach sampling programs for the Baltic and other ecosystems.

This master project aims to explore the spatial and temporal correlation among the cod stomachs and the implications of sampling design and sample size for the estimation of the main processes linked to the implementation of multispecies models. The analyses are expected to yield alternative strategies of stomach sampling in Baltic cod and highlight costeffective sampling

schemes which sampling intensity appropriately quantifies cod predation on clupeids in the Baltic and beyond.

Requirements: good skills in spoken and written English, basic statistical skills and familiarity with R programming (ability to write simple own functions).


Work location: Lysekil

Contacts:

Valerio Bartolino, Researcher
Department of Aquatic Resources, Institute of Marine Research, SLU
valerio.bartolino@slu.se, +46 10 478 40 58

Nuno Prista, Environmental Assessment Specialist
Department of Aquatic Resources, Institute of Marine Research, joint staff
nuno.prista@slu.se, +46104784022, +46725450676

Study on the population structure of herring in the central and western Baltic Sea based on the analysis of growth and otolith shape

Master projedt in Ecology (30-60 credits)

Study on the population structure of herring in the central and western Baltic Sea based on the analysis of growth and otolith shape

Stock assessment of herring in the southern Baltic is currently based on a rigid geographical definition of stock boundaries which allocate herring western of Bornholm Island to the so called Western Baltic Spring spawning herring stock and herring on the eastern side of Bornholm to the large central Baltic herring stock. In reality, in this region herring reproduce in coastal habitats along the southern Swedish coasts and along the entire southern Baltic coast from the western to the eastern limits of the basin giving origin to a number of subcomponents within these two stocks.

The relationships among the different sub-components within and between the two stocks are poorly understood, as well as the level of mixing and geographical extents of overlap between the different components belonging to the two stocks remain unknown. This lack of knowledge on population structure has profound implications for the management of herring in the Baltic, both in terms of diversity and productivity.

This master project aims to evaluate the relationships between some of the main herring spawning components in the southern Baltic Sea to contribute to the harmonization of stock assessment units definitions and population structure. Moreover, the analyses are expected to identify solid baselines for future discrimination of the main herring components occurring in mixed catches of commercial fisheries and scientific survey across this broad geographical region.

Requirements: good skills in spoken and written English, basic statistical skills (familiarity with multivariate analyses is an advantage).
Work location: Lysekil.

Contacts:

Valerio Bartolino, Researcher
Department of Aquatic Resources, Institute of Marine Research, SLU
valerio.bartolino@slu.se, +46 10 478 40 58

Carina Jernberg, Head of Unit
Department of Aquatic Resources, Institute of Marine Research, SLU
carina.jernberg@slu.se, +46 10 478 4025, +46 761-26 80 16

Energy content in the diet of breeding seabirds

Bachelor (15 ECTS) or Master (30/60 ECTS)

Energy content of the diet of Common guillemots in the Baltic Sea

Common guillemots Uria aalge L. (Am. Eng.: Common Murre) are marine piscivorous top predators with a circumpolar Arctic distribution. Long-term studies have shown that they can be important indicators of changes in marine food webs and ecosystems. The largest Common guillemot colony in the Baltic Sea (~ 15 000 pairs) is at the island of Stora Karlsö. Since 1997, a long-term research program is following this colony and collects annual data on survival, reproduction and diet, among other things.

Obtaining high energy food is a prerequisite for successful breeding and survival in Common guillemots. Several studies have shown that the main food in the Baltic Sea is sprat Sprattus sprattus. New data however show that herring Clupea harengus can also be a significant part of the diet. The energy content of herring of different sizes, and the possible energy content differences between sprat and herring is today unknown. The knowledge is important for evaluating the conservation status of Common guillemots in the Baltic Sea and how much fish that must be left in the sea to ensure survival of seabirds.

The degree thesis focusses on analyzing the energy content of the prey fish of Common guillemots. The fish has already been collected by the Institute of Marine Research in Lysekil. The fish will be analyzed using a bomb calorimeter by the student. This work will take place in Ultuna, Uppsala. The data obtained will be analyzed statistically. The project is planned for Bachelor's level (15 ECTS) but can be expanded into a Master's project as well (30–60 ECTS).

Links
www.balticseabird.com
www.storakarlso.se

Contact

Jonas Hentati Sundberg, Researcher
Department of Aquatic Resources, Institute of Marine Research, SLU
jonas.sundberg@slu.se, +46 10 478 40 70, +46 739-38 79 69

Evaluating camera monitoring for breeding seabirds

Bachelor (15 ECTS)  or Master (30–60 ECTS)

Evaluating camera monitoring for breeding seabirds

Common guillemots Uria aalge L. (Am. Eng.: Common Murre) are marine piscivorous top predators with a circumpolar Arctic distribution. Long-term studies have shown that they can be important indicators of changes in marine food webs and ecosystems.

The largest Common guillemot colony in the Baltic Sea (~ 15 000 pairs) is at the island of Stora Karlsö. Since 1997, a long-term research program is following this colony and collects annual data on survival, reproduction and diet, among other things. In 2008, a world unique research facility, the Karlsö Auk Lab, was built in the middle of the colony. Scientists can study breeding birds from the inside of the Auk lab at a very close distance (20 – 30 cm). This opens up for extremely detailed studies to a low disturbance.

This degree thesis is about evaluating a new technology for monitoring breeding success in Common guillemots – through automatic cameras. Today breeding is monitored through daily observations to check which eggs and chicks that are present. The new technology builds on images taken at regular intervals, and at a later stage analysis of the images. If this technology is working, there is a big potential of increasing data collection and reduce time spent close to the birds (which also leads to lower disturbance levels). The field work includes both traditional observations studies and collection and analysis of images.

At least four weeks will be spent at Stora Karlsö for field work. The island has a simple field station in the period May – early July. The student will work with experienced field personnel and a field work coordinator. The project is planned for Bachelors level (15 ECTS) but can be expanded into a Masters project as well (30 – 60 ECTS).

Links
www.balticseabird.com
www.storakarlso.se

Jonas Hentati Sundberg, Researcher
Department of Aquatic Resources, Institute of Marine Research, SLU
jonas.sundberg@slu.se, +46 10 478 40 70, +46 739-38 79 69

Does reed harvesting affect insect production?

Does reed harvesting affect insect production?

In this project you will compare insect biodiversity between two Baltic bays, one where the reed (Phragmites australis) bed has been harvested, and the other un-changed as a control. Over the past years, we have compared changes in bird, fish and macrophyte communities. Now, we will additionally survey insect biodiversity in the same locations. We are looking for a motivated student to collect, process and analyse insect samples, dependent on timing of your thesis.

Background

The common reed (Phragmites australis) is a habitat forming emerging plant found on Baltic and freshwater shorelines. Reed, like trees in a forest, many important ecological functions such as structure, shelter and a source of food for numerous fish, birds, insects and mammals. However, increasing eutrophication has caused reed to invade new habitats and form large monocultures with low biodiversity. The harvesting of reed has the potential to combat monoculture formation and restore habitat heterogeneity, thereby benefiting ecosystems functions and services where reed has become too dense and/or invaded.

Method

In this project, we investigate the impact of reed harvesting on biodiversity by performing surveys of fish, bird, insect and macrophytes in a reed harvested area, and comparing this with the same surveys at a nearby control site. For insects, we will use emergence ans/or swimming traps to collect insects in the two contrasting areas. We are also happy to discuss new or other ideas within the topic of reed harvesting effects on the ecosystem.
Field studies are based in Harg, near Östhammar, with office space available at Ultuna, Uppsala. Feel free to contact with any questions, or if you are interested in doing a bachelor thesis within this project!

Contacts

William Ashworth,Doctoral student
Department of Aquatic Resources, Institute of Coastal Research, SLU
william.ashworth@slu.se, +46 10 478 41 68

Örjan Östman, Senior Lecturer, Director of Studies - basic education
Department of Aquatic Resources, SLU
orjan.ostman@slu.se, +46 10 478 41 53

Competition between perch and roach across sizes and environments–impact on ecological status

Biology 30 credits

Stable isotopes are indicators of individual diet use and can be used to study diet (resource) overlap between species indicate (resource). Perch and roach are the two dominate fish species in Baltic Sea coastal fish communities, and have different ecological functions. Perch is the main predatory fish, but feed on invertebrates as small, whereas roach is an obligate ‘mesopredator’ feeding only on invertebrates. However, as fish change diet over their life-history they compete for common resources at younger ages (sizes). In this project you will study how the diet overlap change across body sizes depend on environmental condition, like watercolor and transparency, temperature and salinity.

To understand how environmental conditions influence the competition and resource use of perch and roach is important to better understand how global change will impact the interaction between our most common fish species, and how management may be adapted to reach good ecological status in coastal areas of the Baltic Sea.

All data has been collected and is ready to be analysed so start time is flexible.
Contact:

Associate professor Magnus Huss, magnus.huss@slu.se

Associate professor Örjan Östman, orjan.ostman@slu.se

Life-history changes of predatory fish in changing environments

Biology 30 or 60 credits

The aim of this project is to investigate changes in perch and pike life history traits to long-term changes in climate and productivity (eutrophication). Whereas the direct short-term impact of environmental variation on life histories are quite well studied, the longer term eco-evolutionary dynamic consequences on predator life-histories are less understood.

To address this you will use back-calculated growth of pike and perch from long-term monitoring data of fish communities in Swedish coastal areas and freshwater lakes. This data serves as great opportunity to develop a framework for a general future understanding of how large scale environmental variation will affect life-history traits and reaction norms of predatory fish in a changing world. This knowledge is both important to understand the long-term anthropogenic impact on natural communities, and is also relevant to reach the environmental targets set within Sweden and the European Union.

Project start is flexible data collection is ready. Therefore a large part of thesis project will be statistical analyses and model simulations.

Contact

Associated professor Örjan Östman, orjan.ostman@slu.se

Using AI to map human activities in the ocean

Masters thesis 30-60 hp

Background

Marine ecosystems are under immense pressure from a wide range of human activities, such as fishing, shipping, coastal development, and pollution, among others. One of the greatest challenges faced by conservation scientists and practitioners is the task of mapping these activities so that we may determine which ecosystems are most threatened and where we should focus our conservation efforts. However, in recent years, exciting developments in the field of artificial intelligence (AI) offer a promising solution to this challenge.

Project description

In this project, the student will use neural networks and satellite imagery to produce maps of human activities in the ocean. The objective will be to map specific activities that are recognizable through satellite images, which may include small-scale fishing, mariculture, and/or oil and gas activities. The study region and scale are flexible, but will ideally include the Western Indian Ocean, the South China Sea, the Gulf of Thailand, and/or the Baltic Sea.

The student should have a strong interest in modelling/machine learning, coding (ideally in R or Python), and conservation. It is also advantageous to have some knowledge of marine ecosystems, but this is not essential. The project may be undertaken at any time and falls within larger ongoing projects in the Baltic Sea, the Western Indian Ocean, and South-East Asia. As such, the student can expect to be involved in a highly collaborative research environment.

Contact

Edmond Sacre

Department of Aquatic Resources, Institute of Coastal Research, Swedish University of Agricultural Sciences

edmond.sacre@slu.se, +46 730855441

Monitoring populations by fishing gear – A camera study of the European lobster

Master thesis 30/60 credits

The European lobster (Homarus gammarus) occurs along the entire Swedish west coast down to the northern part of the Sound, and lives mainly on rocky substrates in crevices and dugouts between rocks and gravel. The lobster population along the Swedish coast is considered to be one single stock, but large local differences in density may occur. Fishing for European lobster is extensive, but catch per effort (the number of lobsters caught per pot) decreased sharply during the 1950s and 1960s and has since remained at a stable low level according to catch data from lobster fishermen in Bohuslän. New legislation limiting the lobster fishery was passed in 2017, yet the stock is still considered to be overfished: The overall stock analysis (Fish Barometer 2024) indicates high fishing mortality over long periods, and low productivity, with the result that the stock is not within safe biological limits. To provide management with a strong basis for decision-making, we are working to increase the knowledge of European lobster biology and behavior.

Every year, the Department of Aquatic Resources (SLU Aqua) conducts a lobster survey in both no-take and fished areas to provide fisheries independent data on biological parameters of the Swedish lobster population. In addition to SLU's survey, volunteer fishermen participate in the citizen science project; LOBSERVE, which enables the collection of catch data and size along a larger geographical area. Lobster catch can be used as an index of density, and thus of stock status, and can be compared between areas and over time if the fishing is standardized and carried out at the same time of year. If a pot is left fishing (soaked) for a longer period, the pot will eventually be saturated as lobsters are no longer attracted to the bait or choose not to enter due to e.g., competition. CPUE needs to be standardized to soak time to be comparable. With the help of a camera study, we want to find out what happens at and around the cage. We want to investigate questions such as

  • What influences a lobster to enter a pot?
  • At what rate is a pot getting saturated?
  • At what point do lobsters stop entering the cage?
  • Do lobsters' propensity to enter a cage with other lobsters differ between fished and no-take areas?

We offer the opportunity to do a degree project with focus on European lobsters, using camera-rigged pots to study the behavior of lobsters around pots and also factors leading to saturation of pots. We are looking for a highly motivated student with an interest in fisheries ecology and animal behavior. Experience with dynamic modelling and R is an advantage. The work includes fieldwork, analysis of collected video material and data analysis. SLU's lobster survey occurs in Lysekil in August, and the student will be part of the crew while deploying the lobster pots rigged for video.

Contact

Hege Sande, hege.sande@slu.se 

Andreas Sundelöf, Andreas.sundelof@slu.se

For more information

Read more about the European lobster at the website Fiskbarometern (text in Swedish) (published by the Swedish Agency for Marine and Water Management)

Read about the species facts at the SLU website Swedish Species Information Centre (in Swedish)

Read the SLU news article about fishing on the European lobster (in Swedish)

Read more about the SLU citizen science project on European lobster (in Swedish)


Contact

Örjan Östman, Senior Lecturer, Director of Studies - basic education
Department of Aquatic Resources, SLU
orjan.ostman@slu.se, +46 10 478 41 53