HABITAT SELECTION DECISIONS IN A MULTIPREDATOR / MULTISPECIES LANDSCAPE

Breeding territory location is a crucial decision in the life of birds, especially in short-lived migrants. Other individuals form a vital component of habitat quality and I investigate habitat selection decisions relative to other individuals and the consequences in terms of reproductive success.

In particular I examine how ”enemies”, both on the same and higher trophic levels, serve as cues and provide information that decreases the focal individual’s uncertainty about the environment. I generally try to use field experiments in my studies, using nest box species, the Pied Flycatcher, redstart and breeding tits, but also the entire avian community response.

This work is done in collaboration with Prof Erkki Korpimäki, Dr. Chiara Morosinotto and Dr Jukka Forsman, in field sites in Oulu and Kauhava, Finland.

 

 

PHYSIOLOGICAL AND BEHAVIOURAL RESPONSES TO EXPERIMENTAL ENEMY RISK

Non-lethal impacts of predation or parasitism risk are typically expressed in terms of altered behaviour or physiology which is costly to the individual. Experimental tests under natural variation in predation risk on mutli-scale level continue to provide new understanding on how animals cope with the risk of being eaten. My focus is on exploiting the unique experimental possibilities of the flycatcher at smaller scales, to investigate old questions with new field experimental methods.

Field work is mainly conducted in Kauhava, Finland

 

INTRA-GUILD PREDATION, THE IMPACT ON INTRA-GUILD PREY

Predators sometimes kill other predators on the same trophic level. This intraguild predation, together with competition, may alter behavioural responses of IG-prey, which may cause trophic cascades, mesopredator release and have significant impacts on prey populations. Spatial outcomes of intra-guild interactions should impact habitat selection decisions of the shared prey of these predators.

Together with Dr. Chiara Morosinotto, Dr. Alex Villers and Prof Erkki Korpimäki, we investigate direct and indirect intra-guild interactions to explain the spatial structure of a avian predator community that includes pygmy owl, Tengmalm’s owl and Ural owl. A three-species intra-guild system at this scale is noteworthy, and a linear settlement sequence makes it particularly suitable for study.

LIFETIME REPRODUCTIVE SUCCESS IN TENGMALM’S OWLS

The trade-offs between investments in current and future reproduction as well as between the quantity and quality of offspring are at the heart of life-history theory. In avian systems, most studies utilize short-term proxies to investigate these life-history trade-offs. This is expected because of the difficulties (time and cost) of collecting long-term data of the actual lifetime reproductive success of individuals. Fortunately, this type of data does exist.

Using brood size manipulations and long-term (16+ years) reproductive output of Tengmalm’s owls we test various predictions of the classic life-history trade-offs. This project was been initiated and maintained by Prof Erkki Korpimäki since the 1980’s. Collaborators are Dr Toni Laaksonen and Dr Michael Greisser.

Owl studies are centred in the famous populations in Kauhava, 

INFORMATION USE IN AVIAN COMMUNITIES

Information gathering in birds continues to be a source of fascination to me. I am trying to take a detailed approach to tease apart the relative importance of different sources of information using small experiments. Work is done on Ruissalo island in collaboration with Dr Toni Laaksonen.

ABOUT ME AWAY FROM THE OFFICE:

The separation between my work and my play is rather fuzzy. But I manage to forget the criticalness of science when travelling, birding or watching sport, particularly rugby.

I was born in Pretoria, South Africa where thanks to my family I began wildlife watching at a young age. My wife and I live semi-permanently in Turku, Finland, with frequent trips to South Africa and Mongolia

 

Research interests

I am broadly interested in questions within behavioural and evolutionary ecology, with emphasis on avian systems. My main research has focussed on habitat selection relative to traditional enemies: competitors, predators and brood parasites. I investigate the interplay of both positive and negative aspects of interactions with enemies and how these influence the decisions of individuals.

Section of Ecology

Department of Biology

University of Turku

FI-20014 Turku, Finland

Email:

firstname.surname@utu.fi

 

Note there is no ”p” in my Thomson

Homepage of

Robert L. Thomson

 

BROOD PARASITISM IN THE REDSTART -CUCKOO SYSTEM

This has largely been a “hobby-project” that has received decreasing amounts of my attention over the years, but will be restarted soon. Redstarts readily nest in boxes in the north and these are frequently parasitised by the Common cuckoo. Redstarts appear to have few of the tradition anti-brood parasite tactics of egg rejection, but seem to suffer little losses to the cuckoo, perhaps due to their recent preference for nest boxes combined with habitat selection strategies.

Dr Jukka Forsman, Jere Tolvanen and I share this passion and a study site in the pine forest around Oulu

DECLINING WADER POPULATIONS OF THE BOTHNIAN BAY

The Baltic populations of Temminck’s stint and Dunlin remain a collaborative research focus. This work was initiated by Drs Kari Koivula & Antti Rönkä in the late 1990’s. The group uses demographic data based on intensive breeding monitoring and capture-recapture to model the factors most important to the long-term survival of these species. In addition, conservation genetics principals are applied and investigated in the populations. The unique breeding systems also allow testing of sexual conflict and reproductive trade-offs in these species.

The group benefits from the abundant expertise of Dr. Veli-Matti Pakanen, population geneticist Dr. Laura Kvist, Prof. David Lank (Simon Fraser University), Nelli Rönkä and Diane M. Tracy.

EXTREME ASSOCIATIONS: SOCIABLE WEAVER - PYGMY FALCON SYSTEM OF THE KALAHARI

Associations between two or more species are a prominent feature of nature. Frequently associations are observed during breeding in animals, and are perhaps most conspicuous when involving birds. An extreme example is the sociable weaver—pygmy falcon. This is a rare association which is essentially obligate for one of the species involved.

Especially in harsh and extreme environments like the Kalahari, animal community persistence and structure is thought to favour positive interactions and close associations.

This study aims to determine the nature of the interaction between these two species, and delve into the demography and life history of the pygmy falcon. In addition, I will explore the keystone nature of sociable weaver colonies to the animal community and ecology in an environment that will become increasingly extreme under global change.

This study is conducted on Tswalu Kalahari, South Africa’s largest private game reserve. With support from the Academy of Finland and the Tswalu Foundation.

MIGRATION OF BARHEADED GOOSE & WHOOPER SWAN

Birds neck-collared by the Wildlife Conservation Society in Mongolia in 2007—2010 are still being resighted at breeding, moulting and wintering sites in Mongolia, India, China and South Korea. We are collecting these records to get a clearer picture of the links between different sites in these countries.

This project is led by Dr. Martin Gilbert, and collated by Losloo Jambal, Selengemurun Dembereldagva and Dr. Amanda Fine.

 

Current Research