Habitat selection of Arctic-breeding waders in relation to palsa mire - a case study in Tavvavuoma, northern Sweden
(2022) BION02 20212Degree Projects in Biology
- Abstract
- Palsa mires are typical wetland landscapes of the Arctic regions, consisting of mosaics of palsas (raised formations of peat and permafrost) and shallow ponds, all embedded in wet mires. These heterogeneous habitats support rich and abundant wader populations, which breed there during the short Arctic summer. Although being threatened by climate change, relatively little is known about the ecological importance of these habitats for breeding waders. In a first step, the relationship between habitat covers and wader diversity was studied, as well as their relationships to the distribution of nine wader species across the wetlands complex of Tavvavuoma in northern Sweden. Thereafter, some specific habitat characteristics that were... (More)
- Palsa mires are typical wetland landscapes of the Arctic regions, consisting of mosaics of palsas (raised formations of peat and permafrost) and shallow ponds, all embedded in wet mires. These heterogeneous habitats support rich and abundant wader populations, which breed there during the short Arctic summer. Although being threatened by climate change, relatively little is known about the ecological importance of these habitats for breeding waders. In a first step, the relationship between habitat covers and wader diversity was studied, as well as their relationships to the distribution of nine wader species across the wetlands complex of Tavvavuoma in northern Sweden. Thereafter, some specific habitat characteristics that were potentially related to the distribution of the Wood Sandpiper (Tringa glareola) were studied in a specific palsa mire in Tavvavuoma. The results show that wader diversity was positively linked to palsa mire extent while being negatively associated with areas covered by birch (Betula pubescens ssp. czerepanovii ). Dunlin (Calidris alpina), Golden Plover (Pluvialis apricaria), Red-necked Phalarope (Phalaropus lobatus), Spotted Redshank (Tringa erythropus) and Wood Sandpiper (Tringa glareola) also had a notable preference for palsa mire. Red-necked Phalarope and Temminck’s Stint presented a positive relationship with waterbodies while the Spotted Redshank had a negative one. The extent of birch forest was negatively associated with Red-necked Phalarope as well. Common Snipe (Gallinago gallinago), Jack’s Snipe (Lymnocryptes minimus) and Ruff (Calidris pugnax) did not show any specific trends with habitat types. The second part of the study confirmed the importance of palsa formations for Wood Sandpiper but could not assess relationships between this species and other environmental characteristics. Further studies will be necessary to investigate in more detail habitat selection of waders in palsa mires. Especially as the progressive disappearance of this habitat will most likely have harmful consequences for breeding populations of waders inhabiting northernmost Fennoscandia. (Less)
- Popular Abstract
- The ballet of waders at the last palsa mires
There are places, far to the north, where wetlands give rise to strange mounds, emerging from the mire and overlooking the flatter tundra landscapes. Local people call them “palsa”, literally meaning: “hummock rising out of a bog with a core of ice”. Indeed, accumulation of ice inside is necessary to make the peat grow several metres high, until the mound edges break up and eventually everything collapses as the ice melts under the summer heat. The remains of palsas are found in the form of small ponds, surrounded by what they have been before crumbling. However, just like phoenix, palsas are reborn from newly formed peat and perpetuate a slow but continuous process. This was before humans... (More) - The ballet of waders at the last palsa mires
There are places, far to the north, where wetlands give rise to strange mounds, emerging from the mire and overlooking the flatter tundra landscapes. Local people call them “palsa”, literally meaning: “hummock rising out of a bog with a core of ice”. Indeed, accumulation of ice inside is necessary to make the peat grow several metres high, until the mound edges break up and eventually everything collapses as the ice melts under the summer heat. The remains of palsas are found in the form of small ponds, surrounded by what they have been before crumbling. However, just like phoenix, palsas are reborn from newly formed peat and perpetuate a slow but continuous process. This was before humans started to mess with the climate and triggered the rapid warming of the northern regions. Now, palsas are relics of a cooler past and are destined to progressively disappear.
But why am I talking about this? It turns out that these particular landscapes host very rich and abundant bird populations, with among the highest densities in all northern Fennoscandia. A group of bird species, commonly known as waders, have an especially strong preference for this habitat type, where they breed during the short Arctic summer. The heterogeneity of the landscape and the favourable conditions for insect populations seems to be the main reasons for this preference. However, there has been limited studied on these aspects, and thus it is a challenge to fully understand how wader populations will be affected by the disappearance of palsa mires.
Therefore, we went to the northernmost part of Sweden, to a place renowned for its many palsa formations and also for the numerous waders that can be found there. Tavvavuoma, located in Swedish Lapland, is the place where we stayed for two weeks, to investigate the relationships between wader populations and the unique palsa habitat typical for the area. Two studies were carried out with the following aims. The first one focused on the habitat selection of nine wader species across all wetlands of the area, while the second part looked for the environmental characteristics that may explained the distribution of a common sandpiper species, the Wood Sandpiper (Tringa glareola), in a specific palsa mire area.
From the results, I have demonstrated that the wader diversity, as well as the abundance of five species, namely Dunlin (Calidris alpina), Golden Plover (Pluvialis apricaria), Red-necked Phalarope (Phalaropus lobatus), Spotted Redshank (Tringa erythropus) and Wood Sandpiper (Tringa glareola), were all positively linked to the extent of palsa mire. The extent of ponds and lakes also had a positive influence on Red-necked Phalarope and Temminck’s Stint (Calidris temminckii), while Spotted Redshank was negatively related to it. On the other hand, the presence of birch forest was negatively associated to wader diversity and to the phalarope species. The second study confirmed the importance of palsa habitat for the Wood Sandpiper, but could not assess other relationships in the study area due to limited observations.
Even if palsas seem to be doomed by the climate change, waders do not have to. Preserving the most suitable breeding habitats of these birds should be a priority, with the support of further studies, to foresee the evolution of their populations and mitigate their overall decline.
Master’s Degree Project in Biology 45 credits 2022
Department of Biology, Lund University
Advisor: Susanne Åkesson
Department of Biology, Lund University (Less)
Please use this url to cite or link to this publication:
http://lup.lub.lu.se/student-papers/record/9078269
- author
- Cistac, Jonathan
- supervisor
- organization
- course
- BION02 20212
- year
- 2022
- type
- H2 - Master's Degree (Two Years)
- subject
- language
- English
- id
- 9078269
- date added to LUP
- 2022-04-08 07:23:44
- date last changed
- 2022-04-08 07:23:44
@misc{9078269,
abstract = {{Palsa mires are typical wetland landscapes of the Arctic regions, consisting of mosaics of palsas (raised formations of peat and permafrost) and shallow ponds, all embedded in wet mires. These heterogeneous habitats support rich and abundant wader populations, which breed there during the short Arctic summer. Although being threatened by climate change, relatively little is known about the ecological importance of these habitats for breeding waders. In a first step, the relationship between habitat covers and wader diversity was studied, as well as their relationships to the distribution of nine wader species across the wetlands complex of Tavvavuoma in northern Sweden. Thereafter, some specific habitat characteristics that were potentially related to the distribution of the Wood Sandpiper (Tringa glareola) were studied in a specific palsa mire in Tavvavuoma. The results show that wader diversity was positively linked to palsa mire extent while being negatively associated with areas covered by birch (Betula pubescens ssp. czerepanovii ). Dunlin (Calidris alpina), Golden Plover (Pluvialis apricaria), Red-necked Phalarope (Phalaropus lobatus), Spotted Redshank (Tringa erythropus) and Wood Sandpiper (Tringa glareola) also had a notable preference for palsa mire. Red-necked Phalarope and Temminck’s Stint presented a positive relationship with waterbodies while the Spotted Redshank had a negative one. The extent of birch forest was negatively associated with Red-necked Phalarope as well. Common Snipe (Gallinago gallinago), Jack’s Snipe (Lymnocryptes minimus) and Ruff (Calidris pugnax) did not show any specific trends with habitat types. The second part of the study confirmed the importance of palsa formations for Wood Sandpiper but could not assess relationships between this species and other environmental characteristics. Further studies will be necessary to investigate in more detail habitat selection of waders in palsa mires. Especially as the progressive disappearance of this habitat will most likely have harmful consequences for breeding populations of waders inhabiting northernmost Fennoscandia.}},
author = {{Cistac, Jonathan}},
language = {{eng}},
note = {{Student Paper}},
title = {{Habitat selection of Arctic-breeding waders in relation to palsa mire - a case study in Tavvavuoma, northern Sweden}},
year = {{2022}},
}