Odonates sampling

Ischnura elegans sampling took place in May and June 2021. Szymon Śniegula with his team sampled the blue-tailed damselflies in Poland and Sweden.

The sampling of Ischnura elegans included both: the odonates pairs (families) sampled for the experiments planned within WP5, and the collection of adult individuals to be analysed within WP3.

Collection of odonates pairs took place in two regions, southern Poland (near Kraków) and southern Sweden (near Malmö), at the following locations:

SOUTHERN POLAND

URBAN PONDS

RURAL PONDS

SOUTHERN SWEDEN

URBAN PONDS

RURAL PONDS

The collected Ischnura elegans families (male, female and their eggs) were transported to the laboratory of the Institute of Nature Conservation of the Polish Academy of Sciences in Krakow. Here Szymon Sniegula together with Gemma Palomar make use of the odonates larvae hatched from the eggs to carry out two experiments.

The larger of the experiments concerns the phenotypic analysis of Ischnura elegans i.e. measurement of the traits responsible for its reproductive success: body weight and growth rate. It involves the study of each of two urban and non-urban odonates populations from both southern Poland and southern Sweden. All larvae, when they reach an appropriate size, are overwintered for several weeks. After the wintering, the larvae divided into 48 groups will be exposed to 2 factors: temperature and (when they reach F0 stage – last stage before emergence) scent of a predator (the invasive species: spiny-cheek crayfish Orconectes limosus). Taking these factors into account, we can calculate that about 2000 larvae are subjected to the experiment:

latitude (2) x urbanization (2x2) x temperature (3: 20°C, 24°C i 28°C) x predator (2, including control groups) = 48 groups x 4 larvae x 10 families ≃ 2000 larvae

The second experiment concerns Ischnura elegans gene expression analysis. In this experiment only rural populations of odonates from two regions (southern Poland and southern Sweden) are being observed. As in the phenotypic experiment, the larvae are exposed to 2 factors: temperature and (after they reach F0 stage) the scent of a predator. The object of this experiment are 1600 odonates larvae:

latitude (2x2) x temperature (2: 20°C i 24°C) x predator (2, including control groups) = 16 groups x 10 larvae x 10 families ≃ 1600 larvae

Once the odonates larvae have reached an appropriate size, they are frozen and transported to the Molecular Ecology Lab of the Institute of Environmental Sciences at the Jagiellonian University, where Marzena Marszałek, supervised by Wiesław Babik, is to check differences in gene expression between groups of individuals.

As per adult Ischnura elegans samples, they are delivered to the Molecular Ecology Laboratory of the Institute of Environmental Sciences at Jagiellonian University, in accordance to the objectives of WP3. The samples were collected in 3 geographical regions, southern Poland (near Kraków), northern Poland (near Szczecin) and southern Sweden (near Malmö), at the following locations:

SOUTHERN POLAND

URBAN PONDS

RURAL PONDS

NORTHERN POLAND

URBAN PONDS

RURAL PONDS

SOUTHERN SWEDEN

URBAN PONDS

RURAL PONDS

The collected Ischnura elegans samples are catalogued and then subjected to further analysis, including DNA isolation and RAD sequencing.

Pictures of damselflies sampling can be seen in our GALLERY.