Thesis (M.A.) -- University of Adelaide, Dept. of Geography, 1979. / Two photos in end pocket.

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The periodic fluctuations in numbers of red grouse (<I>Lagopus lagopus scoticus </I>(Lath.)) populations in Scotland and northern England remain a puzzle to population ecologists despite sustained research. Other workers have suggested that territoriality, philopatry and kin selection, as expressed in the differential behaviour between kin and non-kin, can, through their effects on the efficiency of space use, combine to cause cyclic dynamics. However, since the first preliminary formulation of the hypothesis in 1990, little modelling work has been done on the subject. In this thesis, I present a series of models which explore the plausibility of the kin-selection hypothesis for red grouse populations under different assumption regimes. I first develop, analyse and validate a simple, deterministic model using functions of age structure as indexes of the social and, due to philopatry, spatial attributes of the population. A control version of the model is incapable of cyclic dynamics, while a modification, containing the assumed effects of kin selection, produces cycles of realistic period and amplitude. Parameterisation of the model with field data from two studies in north-east Scotland yields output which resembles the observed dynamics. A more detailed study of the possible effects of kin selection and philopatry on individual requirements for space yields a parameterised response function which is then used to study the dynamics of individual family clusters. A model of the relatively short-term process of family cluster formation demonstrates that continuous changes in crowding may have a discontinuous effect on the ability of clusters to form. A socially and spatially explicit simulation model is finally developed to examine the relative importance of these factors in the long-term dynamics. Based on its results, I conclude that spatial heterogeneity in the activity of animals, caused by clustering, is sufficient to produce cycles and that variations in territorial requirements due to differential behaviour between kin and non-kin can have a secondary, amplifying role in the process.

Farmland bird populations in Europe have been in decline for a long time. Agricultural intensification and growing a large share of crops that provide suboptimal breeding habitat could be the main causes of the observed decline. To explore these possible drivers, I focused on population trends of farmland bird species in different habitats in the Czech Republic over the periods 1982-1990 and 1990-2010. Specifically, I focused on the variability in trends within each species in respect to the differences in landscape management between the lowlands and mid-altitude areas before and after 1990. The expected effect of intensive farming in the lowlands until 1990 was reflected by a strong decline in populations of Northern Lapwing and Yellowhammer. The influence of less intensive farming in mid-altitude areas causing moderate population decline was confirmed rather by shrubs and trees species than farmland specialists. After 1990, less intensive farming in the lowlands should reduce the decline, which may have occurred, but compelling comparison of population trends between the two time periods was not possible for most species due to the lack of data. On the contrary, more intensive population decline in mid-altitudes after 1990, which should be the response to arable land abandonment, was not...

Studier har visat att fåglar påverkas av ökade ljudnivåer och ljudfrekvenser (Kociolek et. Al. 2011). Olika fågelarter skiljer sig i känslighet vid störning av ljud. Vissa arter kan anpassa sig och förändra sin kommunikation till den nya ljudsituationen. Andra kan påverkas i sin fortplantning då lätet är en väsentlig del av partnerkommunikationen. Vidare kan vissa fågelarter behöva flytta till ett annat habitat på grund av att de inte kunnat anpassa sig (Gill et. Al. 1999, Helldin 2004). Fågelinventeringar för nybyggnation av motorväg E6 Tanumshede, Norra Bohuslän redovisar antalet fåglar innan och efter motorvägens öppnande den 7 juli 2015. Hypotesen att ljudnivåer skiljer sig i nivå med avstånd från motorvägen och jämfört med referensskog bekräftades. Däremot visar analyser med en ANOVA inte på att antalet fåglar är påverkat av en högre ljudnivå. En del fågelarter uppvisar en signifikant ökning eller minskning i antal, vid analys av dessa fåglars kommunikationsfrekvenser kunde ingen signifikant skillnad ses. Det har inte funnits tillräckligt underlag för att göra en bedömning av mer sällsynta arter som eventuellt skulle vara mer påverkade av en förändrad ljudbild. / Studies have shown that birds are affected by increased noise levels and changes in sound frequencies (Kociolek et al. 2011). Different bird species differ in their sensitivity to noise disturbance. Some species can adapt and change their communication to the new sound situation, whereas others may be affected in their reproduction because sound in an essential part of partner communication. Furthermore, some species may need to move to another habitat because they could not adapt to the new sound situation (Gill et al. 1999, Helldin 2004). Birds inventories for the new motorway construction, E6 Tanumshede North Bohuslän, report the numbers and species of birds before and after the opening of the motorway on July 7, 2015. The hypothesis that noise levels differ at the distance from the highway and compared to reference forests were confirmed. On the other hand, analyses with an ANOVA do not indicate that the number of birds is affected by a higher noise level. Some bird species showed a significant increase in numbers after roadwork, whereas others decreased. No significant difference could be seen in the analysis of these birds’ communication sound frequencies. There has been insufficient support to make an assessment of more rare species that might be more affected by a changing noise levels.

The purpose of the study is to determine how the population of the ruff in Sweden has changed over the past 20 years and which reasons for the changes, if any, there are. The study also includes how the tourism regarding the ruff in Sweden is today and how it could be developed. The study is based on non-fiction literature, reports, diagrams and interviews. The population of the ruff in Europe has declined over the past years. In Sweden, the breed is classified as vulnerable on the IUCN Red list of threatened species due to the fast decline. The results show that the population of the ruff has changed in the whole country of Sweden. Today almost 99% of the population lives on tundra and wetlands in northern Sweden. Most of the decline has occurred in the south of Sweden where the population almost is extinct. In northern Sweden, the population also has declined but not as much as in the south. Nowadays the ruff only breeds in 8 out of 22 counties it used to occur in. Reasons of the decline are primarily changes in habitats, drainage of watercourses and wetlands, urbanization, agriculture and forestry. The decline also depends on changes along the migration routes and in northwest Africa where the breed winters. Also, climate change and higher predation are reasons for the decline. No tourism with focus on the ruff exists in Sweden today. There is a potential in developing a specific tourism focused on the ruff lek.

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Paukščiai laikomi gerais biologinės įvairovės ir aplinkos kokybės indikatoriais. Kasmetinės paukščių apskaitos vykdomos visose ES šalyse ir kai kuriuose kitose Europos valstybėse. Paukščių populiacijų gausos indeksai apjungia informaciją apie atrinktų paukščių rūšių populiacijų bendrus gausos pokyčius. Paukščių rūšys parenkamos atsižvelgiant į šalies paukščių rūšinę sudėtį. Europoje plačiausiai naudojami įprastų rūšių paukščių indeksai, kurie yra paremti paukščių populiacijų gausos pokyčių tendencijų vidurkio skaičiavimu. Jungtinės Karalystės ir Nyderlandų mokslininkai pirmauja skaičiuojant ir naudojant paukščių populiacijų indeksą biologinei inikacijai vertinti. Plačiai paplitusių ir įprastų miško paukščių populiacijų tendencijos rodo – kad jie visoje Europoje nežymiai nyksta. Agrarinio kraštovaizdžio paukščių populiacijų indeksai atskleidžia, kad Vakarų Europoje paukščių populiacijų sumažėja per pastaruosius 25 m. apie 40 proc., miškingo kraštovaizdžio- apie 20 proc., o dažnų paikščių populiacijų gausa beveik nepakyto. Surinkta po įvairius šaltinius išsibarščiusi informacija rodo, kad svarbiausia paukščių nykimo priežastis yra nepakankamai palanki žemės ir miškų ūkio politika. / Birds are considered as good biodiversity and environment quality indicators. Annual bird surveys are being performed in all European Union and in some other European countries. Bird population indices integrate information on changes of numbers of populations of selected species. National lists of the species to be used when calculating bird population indices are formed depending on country specific bird fauna. In Europe common bird indices are used most widely. They are based on calculation of average changes of local population numbers. Scientists of United Kingdom and the Netherlands are leading methodological studies when calculating bird population index with the goal of biological indication. Trends of the common forest bird populations show their insignificant decrease in all the Europe. During recent 25 years in West Europe indices of bird populations of high specialised species discover their big decrease (about 40 %) in agricultural landscape and reasonable decrease (about 20 %) in forest landscape. Meanwhile populations of very common non-specialised species have remained near stabile. Collected rather scare and dispersed scientific literature shows that not enough environmentally friendly agriculture and forestry have to be considered as a main reason of bird population decline in Europe.