Biology Education

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 asks 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 2024, and the student will be part of the crew while deploying the lobster pots rigged for video.

Contact: Hege Sande, hege.sande@slu.se or Andreas Sundelöf, Andreas.sundelof@slu.se

For more information:
https://www.fiskbarometern.se/rapport/2023/species/Europeisk%20hummer
https://artfakta.se/artinformation/taxa/Homarus%20gammarus-217764/detaljer
https://www.slu.se/ew-nyheter/2024/1/bra-ar-for-hummerfiske–daligt-ar-for-hummern/
https://www.slu.se/lobserve

Would you like to contribute to our understanding of the effects of human activities on species genetic diversity? Why not join our team to study the impact of forest management on an endangered saproxylic beetle?

Forestry is a source of renewable raw materials and bioenergy but also has a key role in the conservation of insects and other organisms attached to dead wood. However, the Swedish Forestry Agency’s forecasts showed that many biologically valuable forest types, including older pine forests, risk being displaced by more homogeneous forest landscapes dominated by younger, dense stands of spruce. Wood-living insects represent excellent indicators of biodiversity in forestry and nature conservation. In pine forests, the rare pine wood-living longhorn beetle Tragosoma depsarium has great potential as a signal species for valuable habitats and is a Swedish conservation priority species. It has specific habitat requirements, especially in sunlit older pine forests, developing on coarse, dead pine logs, and has an important role in the ecosystem by breaking down deadwood. However, little information is known on its true distribution and population abundance in relation to available deadwood substrates. The species likely has a highly fragmented population distribution in major parts of Sweden, due to fragmentation of its habitat though modern forestry. T. depsarium could thus represent an ideal model species to study the effects of habitat fragmentation on genetic diversity and gene flow, as we now have excellent tools for systematic monitoring and collection:

We seek motivated Masters students to join our project which intends to (i) describe the genetic diversity and population structure of T. depsarium in Sweden and (ii) determine if populations have suffered loss of genetic diversity due to forest management and isolation. During the summer 2021, the geographic distribution of the beetle in Sweden was assessed at a large scale through extensive pheromone trapping, and several populations were sampled along its distribution range. DNA was extracted for each individual and sent for RAD sequencing. The student will have the opportunity to analyse RADseq data from raw data to more advanced analyses, including population genetics. The study could be performed as a standalone bioinformatics study based on existing RADseq data, but also include hands-on experience with field sampling and DNA extraction techniques based on additional studies that will be performed in 2024. The results will be useful for implementing more efficient conservation management strategies for this beetle in Sweden.

This project is a collaboration between researchers at SLU and the University of Helsinki. The project also includes continued pheromone-based surveys and landscape studies of T. depsarium, which will be pursued in parallel conservation projects in 2024.

Duration and credits

Bioinformatics studies on sequenced materials could start immediately, as early as possible from April. If you would be interested in getting involved in active sampling and DNA extractions, the best sampling time is generally during July with preparations starting in late May or early June. Laboratory work with samples could start in the autumn semester in September. Credits: Masters corresponding to 30-45 credits.

Required qualifications and learning goals

You have a keen interest in evolutionary ecology, genetics and conservation biology. Through this project you have the opportunity to develop your skills and experience in practical entomology and field sampling, hands-on genetic techniques, bioinformatics, biological conservation, population genetics and other statistical analyses. You don’t need prior experience from bioinformatics. The work environment will be in English. The project has already started but you will have the opportunity to suggest studies and approaches of your own interest!

Contact Audrey Bras, Research Centre for Ecological Changes, University of Helsinki, Finland (audrey.bras@helsinki.fi) https://www.helsinki.fi/en/researchgroups/life-history-evolution/people

or Mattias Larsson (mattias.larsson@slu.se) for more information.

We are seeking a Master’s student for a 30, 45, or 60 credit thesis opportunity starting Spring / Summer 2024 to explore the relationship between ambient weather conditions, floral microclimates and resources, and pollinators. Field work will involve floral resource collection and pollinator identification and sampling.

Background:

Climate change is increasing the frequency and magnitude of heat waves, a cause of severe stress to insect pollinator communities. Pollinators can to some extent self-regulate their body temperatures but are also known to depend on their thermal environment. However, conservation efforts to mitigate the impact of heatwaves on biodiversity and related ecosystem services are still lacking.

Semi-natural grasslands are habitats which provide diverse resources for insect pollinator nesting and foraging. These grasslands can vary in characteristics such as topographic orientation, tree and shrub cover, and types of vegetation, all of which can create microclimates which buffer or amplify ambient temperatures. We hope to determine which landscape features, via their influence on microclimate, are related to pollinator distribution and behavior.

Project description:

In this project we will evaluate the potential of microclimates created by heterogeneity in semi-natural grassland vegetation and topography as buffers against high ambient temperature conditions and a means of environmental temperature regulation for pollinators. We will use unmanned aerial vehicles (UAVs) to capture the microclimates, vegetation structure, and terrain of semi-natural grasslands. We will explore pollinator distribution, behavior, and activity in relation to these microclimates and determine the effect of microclimates on floral resource quality and plant surface temperatures.

You will join us in the field in identifying pollinators such as bees, butterflies, and hoverflies, as well as taking measurements and samples from flowering plants. You will learn to develop a research question of your own within the project framework and develop important scientific skills as part of your Master’s studies. 

Are you interested?

If you would like to know more about this position and working with insect pollinators please contact Arrian Karbassioon (arrian.karbassioon@cec.lu.se) and William Sidemo Holm (william.sidemo_holm@cec.lu.se) for more information. 

Pollinators in agricultural landscapes suffer from an increasingly intensive agriculture and loss of semi-natural habitat, which has resulted in lack of flower resources. To support pollinators, flower plantings have been suggested as a promising conservation action, and flower plantings have indeed been found to increase both abundances and diversity of several pollinator groups. However, the knowledge is still limited about how well different flower mixes establishes in different planting contexts (e.g. soil type, moisture, shade/sun exposed areas), how these contexts can affect flowering phenology and hence which pollinator species that are supported.

In Sweden, a new agricultural policy (implemented from EU´s Common Agricultural Policy 2023-2027) has been implemented that promotes flower plantings. It is a voluntary choice for farmers; however, it is an attractive choice since the planting of flower mixtures in set-aside land (in contrast to no planting) reduces the amount of land farmers need to take out of production. The flower planting project “Hela Skåne blommar” and “Hela Sverige blommar”, run by Hushållningssällskapet (https://hushallningssallskapet.se/forskning-utveckling/hela-sverige-blommar/), helps farmers with flower mixtures and in 2022 they already involved 225 farmers in Skåne and 800 in Sweden, and covered altogether 2 750 ha farmland.

Despite the large scale of the flower plantings, there has been no thorough evaluation of which factors that impact establishing rates or the visiting pollinator community. In this project, you will work together with researchers and stakeholders (Hushållningssällskapet) to evaluate how different seed mixtures establishes and their flowering phenology in different contexts, and which pollinators that visit the flower plantings in different replicated setups. The time and scale of the project and the specific research question can be modified depending on your interest and if the project is a BSc or MSc project. Fieldwork will involve plant and insect surveys and can be conducted during the flowering of the different seed mixtures (June – August) in favourable weather conditions, or later in autumn or next spring depending on the specific research question.

Are you interested? Please contact:

Ulrika Samnegård ulrika.samnegard@biol.lu.se or

Maj Rundlöf maj.rundlof@biol.lu.se