Winck, G. R., dos Santos, T. G. & Cechin, S. Z. 2007: Snake assemblage in a disturbed grassland environment in Rio Grande do Sul State, southern Brazil: population fluctuations of Liophis poecilogyrus and Pseudablabes agassizii. — Ann. Zool. Fennici 44: 321–332.

A mark–recapture study of a snake assemblage using pitfall traps with drift fences was carried out in a disturbed grassland environment (e.g. cattle breeding and cultivations), located in the Pampa Biome, in the central region of the Rio Grande do Sul State, southern Brazil. From February 2001 to January 2004 we caught 272 snakes belonging to 20 species from the following families: Elapidae (5%), Viperidae (10%), and Colubridae (85%). The assemblage had a unimodal seasonal pattern of activity, and the highest number of captures occurred between September and May. There was a positive and significant correlation between the number of captures and monthly minimum and maximum average temperatures. Recruitment was observed from January to April. During the study, the area was affected by human activities, which altered the community structure: Pseudablabes agassizii was negatively affected by habitat devastation while Liophis poecilogyrus took advantage of this. Our results reinforced the impression that Pseudablabes agassizii is a habitat specialist species. We extend the understanding of the susceptibility of this species to environmental destruction in open natural environments of South America, and propose its use as a potential bio-indicator of the Pampa biome. We also discuss the importance of conservation strategies for snakes in grasslands of southern Brazil.

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Yalçin-Özdilek, S. 2007: Status of sea turtles (Chelonia mydas and Caretta caretta) on Samandag Beach, Turkey: a five-year monitoring study. — Ann. Zool. Fennici 44: 333–347.

Samandag Beach in Turkey is one of the three most important nesting beaches in the eastern Mediterranean for the critically-endangered green turtle (Chelonia mydas), and is also a nesting area for the loggerhead turtle (Caretta caretta). In this study, the nesting characteristics of green and loggerhead turtles on Samandag beach were determined during the nesting season from 2001 to 2005. During the five-year monitoring, the mean green and loggerhead turtle nest numbers were 121 (range = 16–325) and 11 (range = 7–20), respectively. The mean ratio of non-nesting emergence to nesting emergence (1.6) was lower than the ratio reported in previous studies. The green-turtle nest density on Samandag beach (14 km), and Seyhhizir beach (4.1 km), was 9.3 (range = 1.1–23.2) nests/km and 23.5 nest/km (range = 3.4–64.4), respectively. Loggerhead turtle emergence was randomly distributed, the emergence of green turtles (94.1%), however, was concentrated approx. 3 km north and 3 km south of the Asi River. The emergence of both species took place mainly in July. The average hatching success of green and loggerhead turtles was 70.38% and 71.8%, respectively, with minimum and maximum incubation durations of 43–67 and 44–61 days, respectively.

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Milonoff, M., Nummi, P., Nummi, O. & Pienmunne, E. 2007: Male friends, not female company, make a man more attractive. — Ann. Zool. Fennici 44: 348–354.

Mate choice is often considered independent, but recently attention has been paid to social influences on mate preference, i.e. non-independent mate choice. Especially in humans, mate preference may be influenced by reactions and opinions of other individuals. One type of non-independent mate choice documented in a wide variety of taxa is copying the choice of other females. Although humans may not be a species in which mate choice copying is most likely to occur, many aspects of the human mating system may have favored mate choice copying, and the possibility of copying in humans has been suggested. Apart from other women s choice, women can use evaluations by other men as a mate choice criterion, because a man s friends can reveal a lot about his social skills and status. We used image processed photographs to study the effect of male friends and the occurrence of mate choice copying in teenage females. We tested if male or female company affected the attractiveness of men in photos or influenced the respondent s willingness to date the men. A positive effect of male company was detected, but no indication of mate choice copying was found. During the evolution of human social skills, a support group and recognized status within it may have been important resources for raising offspring. Although no indication of mate choice copying was found, copying in humans may be a complicated process, and it may appear in circumstances different from our test arrangement.

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Usenius, T., Mustonen, A.-M., Usenius, J.-P., Hyvärinen, H., Sipilä, T., Koskela, J. T. & Nieminen, P. 2007: Magnetic resonance imaging and its applications in morphological studies of pinnipeds. — Ann. Zool. Fennici 44: 355–367.

The Saimaa ringed seal (Phoca hispida saimensis) is an endangered endemic subspecies of Lake Saimaa, Finland. Due to its threatened status, the morphology and physiology of the subspecies cannot be studied using live individuals. Magnetic resonance imaging (MRI) is an accurate research method to study normal anatomy and pathology of the subspecies. A female seal cadaver was examined with MRI in three orientations. Morphological structures were identified and verified by reference slice sectioning and dissection. The results provide a morphological MRI reference database for ringed seals and for other pinnipeds. Moreover, pathological and possibly infectious lesions were visible in the blubber and in the apex of the lung. In addition to morphological studies of pinnipeds, MRI can supplement conventional autopsies.

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Ljetoff, M., Folstad, I., Skarstein, F. & Yoccoz, N. G. 2007: Zebra stripes as an amplifier of individual quality? — Ann. Zool. Fennici 44: 368–376.

Amplifiers belong to a class of signals that alone do not indicate an individual's quality, but through design they improve the receiver's ability to assess pre-existing cues and signals. Amplifiers are cost free to produce and maintain, but may yield disadvantages to the individuals that are compelled to reveal their inferior quality. We suggest that zebra stripes, combined with the movement and proximity of other individuals with the same pattern, might function as an amplifier of the individual's escape potential. As a zebra flock is set in motion by predators, stripes may facilitate ascertainment of the quality of the moving individuals (i.e., their escape potential) relative to other individuals in the flock. We tested whether the suggested relationship between stripes such as that of the zebra and quality ascertainment might occur by constructing animations involving 5 moving objects, with one object moving differently from the others. A test panel was asked to identify the deviant object in 4 animations, each of the 4 animations having objects with a different color pattern (striped, black, gradient and spotted). This study lends support to the hypothesis as behaviorally deviant objects were easiest observed in "flocks" of zebra striped objects. Thus, zebra stripes may make odd individuals more visible rather than making them less distinguishable.

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Carrillo, C. M., Moreno, E., Valera, F. & Barbosa, A. 2007: Seed selection by the trumpeter finch, Bucanetes githagineus. What currency does this arid-land species value? — Ann. Zool. Fennici 44: 377–386.

We tested the hypothesis that in harsh environments seed contents, specifically water, and handling time will determine food preferences in an arid bird species, the trumpeter finch. Rape (69.9%) and canary (23.9%) were the most commonly consumed seeds. Mean handling time differed among the tested seed types. There existed a non-linear inverse relationship between mean handling time of different seeds and their selectiveness by individuals. Data estimated from five hypothetical diets and their respective nutritional intakes indicate that this arid land passerine selects a balanced diet optimizing energy and total water intake (energy and water gain per unit of time), rather than a diet that maximizes just energy intake. For birds inhabiting arid and semiarid habitats, food selection should be highly adaptive as selected food items must maximize energy intake rate, but also must contain or produce adequate water to satisfy metabolic requirements.

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Eleftherakos, K., Sotiropoulos, K. & Polymeni, R. M. 2007: Conservation units in the insular endemic salamander Lyciasalamandra helverseni (Urodela, Salamandridae). — Ann. Zool. Fennici 44: 387–399.

Lyciasalamandra helverseni (Caudata, Salamandridae) is the only exclusively insular representative of the genus recently defined as Lyciasalamandra. The species is endemic to a three-island group in the southeast Aegean Sea: Kasos, Karpathos, and Saria (Greece). Tissue samples of Lyciasalamandra helverseni were collected from specimens at six localities on three islands, along with several outgroups. Sequences of two mitochondrial genes (cytochrome b and 16S rRNA), as well as frequencies of 18 allozyme loci, were used to describe levels and patterns of genetic variation, identify possible evolutionary units, and investigate issues of their conservation status. Two major clades of L. helverseni, displaying considerable amount of genetic differences, were found in both analyses. These clades, which have been separated since the late Pliocene, constitute separate evolutionary units and correspond to populations from the islands of Kasos and Karpathos, respectively. The particularly high interpopulation differentiation within relatively short geographical distances, especially in the island of Kasos, implies long-term isolation in fragmented habitats. Severe bottlenecking is proposed to have resulted in the observed low levels of polymorphism of local populations, while inbreeding and low population size might explain the observed lack of heterozygotes. Conservation implications are discussed, particularly in the case of Kasos, where extensive overgrazing of pasturelands has contributed to degradation of the habitat.

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