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1

Niche Dynamics and Biodiversity : Many Rodent Species on One Marshy Meadow

Jancewicz E., Gliwicz J.

Polish Journal of Ecology

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2017

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Vol. 65, nr 4

371--379

EN

The ecological niche of a species is determined by its tolerance to environmental factors and by interactions with other species, particularly those using the same resource. We assessed spatial niches of four rodent species coexisting in one meadow habitat within the Białowieża Primeval Forest. Niche characteristics were based on the valorisation of the habitat around live-trapping sites visited by rodents during seven years of the study. The population size of each species was monitored and expressed as an average annual density. The root vole Microtus oeconomus was the most numerous and dominant species, with its density widely fluctuating due to the temporal increases of predation pressure exerted by the weasel Mustela nivalis. During the study period, the spatial niche of the root vole was nearly constant, with only significantly increased tolerance towards shrub covered sites at times of its high population density. However, even a slight niche expansion of the highly abundant root voles displaced accompanying species: the bank vole Myodes (Clethrionomys) glareolus, the yellow necked mouse Apodemus flavicollis and the striped field mouse A. agrarius, from their preferred sites and efficiently decreased rodent species diversity in the studied habitat. This study illustrates a possible mechanism of the direct effect of predation on the dominant prey species population and indirect one on the species diversity changes over ecological time.

2

Mosasauroid predation on an ammonite – Pseudaspidoceras – from the Early Turonian of south-eastern Morocco

Gale A. S., Kennedy W. J., Martill D.

Acta Geologica Polonica

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2017

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Vol. 67, no. 1

31--46

EN

A juvenile specimen of the ammonite Pseudaspidoceras from the Early Turonian of the Goulmima area in the Province of Er-Rachida in south-eastern Morocco shows clear evidence of predation by a tooth-bearing verte-brate. Most of the body chamber is missing, as a result of post-burial compactional crushing. The adapertural part of the shell on the left flank of the surviving fragment of body chamber bears six circular punctuations; the right flank four. These are interpreted as the product of a single bite by a mosasauroid, probably a Tethysaurus. The taxonomy of the Goulmima Pseudaspidoceras is discuused in an appendix.

3

Free-ranging domestic dogs (Canis familiaris) in Central Poland: density, penetration range and diet composition

Krauze-Gryz D., Gryz J.

Polish Journal of Ecology

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2014

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Vol. 62, nr 1

183--193

EN

The aim of this study was to assess the density and diet composition of free-ranging dogs in Poland. The study was conducted in a field and forest mosaic in the central part of the country in the years 2005–2011. The density of the free-ranging dogs was assessed during night counts along repeated transect routes. The number of dogs seen and the feasible observation area were recorded to calculate density index for each control. The day and night counts captured data on group composition and penetration range. Diets were studied through scat analyses. The dog density ranged from 2.2–3.1 ind. km-2 depending on the area. Most dogs were observed alone, and 40% formed groups of 2 to 5 dogs. Most groups were recorded close to buildings, but the group organisation changed (especially during the daytime) with increasing distance from the buildings: 35% of dogs in the village were in groups, but 55% of dogs formed groups at a distance of more than 100 m from the buildings. The night proportion of dogs in groups was approximately 50%, regardless of the distance. Their scats contained mostly cereal given by farmers. The prey remains were game species: roe deer (1.3% of occurrences in summer and 12% in winter), brown hare (3–4%), small mammals (5–9.5%) and birds (approx. 1.5%). The study demonstrated that the abundance of dogs in the rural areas of central Poland may play an important role in the ecosystem.

4

Przyrodnicze i ekonomiczne uwarunkowania gospodarki stawowej w rezerwacie ornitologicznym „Stawy Raszyńskie”

Walczuk T., Romanowski J.

Woda-Środowisko-Obszary Wiejskie

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2013

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T. 13, z. 4

175--184

PL

Podstawową funkcją stawów rybnych jest produkcja żywności, jednak ostatnio coraz więcej uwagi poświęca się ich roli w retencjonowaniu i ochronie jakości wody oraz w utrzymaniu bioróżnorodności. Stawy rybne są m.in. ważnym siedliskiem ptaków wodno-błotnych, nierzadko stanowiących swego rodzaju „wyspy bioróżnorodności” w krajobrazach przekształconych przez człowieka. Przykładem wielofunkcyjnego gospodarstwa stawowego są „Stawy Raszyńskie” – zwarty kompleks stawów karpiowych założonych w XVIII w., objęty od 1978 r. ochroną w formie rezerwatu przyrody „Stawy Raszyńskie”. Celem ochrony jest zachowanie cennego siedliska lęgów rzadkich gatunków ptaków oraz zapewnienie żerowisk i miejsc odpoczynku ptaków przelotnych. Wprowadzenie ochrony rezerwatowej znacznie ogranicza możliwości prowadzenia rentownej produkcji karpia (brak możliwości renowacji stawów, zmniejszanie się lustra wody). W ostatnich latach dodatkowym czynnikiem negatywnie wpływającym na jego produkcję było powiększenie się kolonii rozrodczej kormoranów Phalacrocorax carbo na Stawie Falenckim. Kolonia, założona przez kormorany ok. 2007 r., rozrosła się do ok. 100 par lęgowych w 2012 r. Równolegle w tym samym okresie zwiększały się straty w produkcji karpia, które w 2011 r. osiągnęły poziom ok. 76% materiału zarybieniowego narybkowego. Zastosowanie w 2012 r. kompleksowej ochrony stawów przed drapieżnictwem kormoranów doprowadziło do zmniejszenia strat w tym roku do poziomu 58,9% materiału zarybieniowego. Autorzy omawiają ścieżkę legislacyjną, dopuszczającą redukcję liczebności kormorana oraz przedstawiają skuteczność aktywnych metod ukierunkowanych na zahamowanie drapieżnictwa kormoranów.

EN

The main function of fish ponds is food production, but recently more and more attention is being paid to their role in water retention, quality protection and maintaining biodiversity. Fish ponds constitute a very important habitat for water birds, being often a type of “biodiversity islands” among the landscape modified by people. An example of a fish farm playing such a multifunction role is “Stawy Raszyńskie”, a compact complex of carp ponds, established in the 18th century, since 1978 protected in a form of an ornithological nature reserve “Stawy Raszyńskie”. The main goal of protection is the preservation of valuable breeding sites of rare bird species and providing feeding sites and resting place for migratory birds. The introduction of nature protection significantly limits profitable carp production (no possibilities of pond renovation, decreasing water surface). An additional factor, which negatively influences fish production has appeared recently. This is the increasing nesting colony of cormorants Phalacrocorax carbo, situated on the island of Falencki Pond. The colony, set up by cormorants about the year 2007, enlarged to about 100 breeding pairs by the year 2012. Simultaneously, carp production recorded increasing losses which achieved 76% of fish fry in 2011. The implementation of complex protection measures against cormorants’ predation in 2012 led to a decrease of losses in the same year to 58.9% of fish fry. Authors discuss the legislation leading to the reduction of cormorants’ number and present the effectiveness of active methods focussed on the mitigation of cormorants’ predation.

5

Survival chances of ground nests in a meadow habitat : a case study in Vrana Lake Nature Park (Mediterranean region, Croatia)

Purger J., Muzinić J., Purger D.

Polish Journal of Ecology

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2012

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Vol. 60, nr 1

207-212

EN

The number of ground-nesting bird species in meadows, one of the most vulnerable habitats in the ornithological reserve of Vrana Lake Nature Park has decreased in recent decades. Nest survival rates were investigated in meadows and reed beds using nest predation experiments in late March and in May 2005. Predators damaged 18% of the 50 artificial nests placed in the pasture meadow habitat in March and 22% in May. Daily survival rate of nests were found to be similar in March (97%) and May (96%). In May, 64% of 25 nests located in the reed bed were discovered by the predators, with the daily survival rate of nests (90%) being significantly lower than that of nests in the nearby meadow. The results suggest that the reasons for the decreasing number of nesting bird species may be - instead of the pronounced presence and activity of predators in the area - the shrinkage of meadow area, the lack of buffer zone, the proximity of agricultural lands, and disturbance caused by intensive grazing.

6

The influence of nest placement on breeding success of the Blackcap (Sylvia atricapilla L.) in two different forest habitats

Zieliński J.

Polish Journal of Ecology

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2011

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Vol. 59, nr 2

391-401

EN

One of the hypotheses to explain a lack of relationship between nest location and breeding success of passerine birds predicts that in an environment characterized by a high diversity of predators that use a variety of foraging strategies, clutches in different locations and degrees of concealment may be equally subject to destruction. In this study I assumed that the impact of nest location on breeding success of the Blackcap Sylvia atricapilla would differ in habitats characterized by significantly different species richness and, consequently, population density and species diversity of potential predators. Thus, I expected that the influence of the nest location and particularly its concealment on breeding success of the Blackcap would be more significant in a habitat characterized by the overall low biotic diversity and low vegetation density. The study was conducted in two forested areas located in central Poland - managed pine forest characterized by low biodiversity and vegetation density and floodplain forest consisting of much higher biodiversity and having higher stand density. I assessed the influence of Blackcap nest placement (concealment, height above the ground, nest plant height, distance from the nest to the closest edge of the nest plant) on breeding success. Among the analyzed parameters, only nest concealment had a significant impact on breeding success. This conclusion, however, pertains only to the pine forest, where successful nests were better concealed than nests with clutch losses. Similar relationships were found in the floodplain forest area, but they were not statistically significant.

7

Kiss of death of a hunting fish : trace fossil Osculichnus labialis igen. et isp. nov. from late Eocene - early Oligocene prodelta sediments of the Mezardere Formation, Thrace Basin, NW Turkey

Demircan H., Uchman A.

Acta Geologica Polonica

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2010

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Vol. 60, no. 1

29-38

EN

The trace fossil Osculichnus labialis igen. et isp. nov. occurs as hypichnial pairs of uneven bilobate mounds in early Oligocene prodelta sediments of the Thrace Basin. Osculichnus is generally elliptical or crescentic in outline and has two lip-like lobes: a smaller and a larger one, which are separated by an undulate furrow. Herein, it is interpreted as a hunting trace (praedichnion) of a fish penetrating a surficial sand layer and into an underlying mud horizon. The fish hunted for small endobenthic bivalves and perhaps other invertebrates such as polychaetes. Penetration into surficial mud rather than sand resulted in poorly preserved variants of this trace fossil, whose median furrow is commonly not visible. The probability of fish trace makers is supported by experiments.

8

The effect of mowing on next-year predation of grassland bird nests : experimental study

Ejsmond M.

Polish Journal of Ecology

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2008

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Vol. 56, nr 2

299-307

EN

The effect of mowing on nextyear nest predation was studied in grassland areas on the outskirts of Cracow (south Poland). In 2004 and 2005, nesting success at three sites with two plots each - one unmowed for 2.3 years and one mowed every year - was assessed experimentally with artificial nests baited with two Japanese Quail Coturnix japonica L. eggs. Biomass samples were collected for estimations of the standing crop of vegetation. Mowing was found to be correlated with nest predation pressure on the unmowed plots in two meadows that had greater vegetation cover. At the third site, nest predation and vegetation cover did not differ between the mowed and unmowed plots. All selected sites were classified as Arrhenatherum elatius grassland. Also birds communities of study sites were similar in regard to occurrence of small ground-nesting passerine species: Grasshopper Warbler Locustella naevia Bodd., Reed Bunting Emberiza schoeniclus L., Whinchat Saxicola rubetra L., Yellow Wagtail Motacilla flava L. Artificial nests were destroyed mainly by corvids and only few percent were recognized as destroyed by mammals. The intensity of nest destruction differed greatly between years, probably because Magpies Pica pica L. were less active in 2005.

9

Reproduction and behavior of plateau pikas (Ochotona curzoniae Hodgson) under predation risk: a field experiment

Yang Shengmei, Yin Baofa, Cao Yifan, Zhang Yanming, Wang Jinlong, Wei Wanhong

Polish Journal of Ecology

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2007

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Vol. 55, nr 1

127-138

EN

The mixture of the feces and urine of the red fox (Vulpes vulpes Linnaeus) was used to increase the perception of predation risk of plateau pikas (Ochotona curzoniae Hodgson) in the field. The influence of the predation risk on the reproduction and behavior of plateau pikas was examined through comparing reproductive characteristics and five different kinds of behavior between treatment and control plots. The results showed that 1) the body weight of the pikas was not significantly different between treatment and control plots. 2) The reproductive period of the pikas extended from March to later August in both treatment and control plots. The pregnant ratio, developed testes ratio, reproductive success and sex ratio of the pikas were not significantly different between the treatment and control plots. 3) The pikas increased their observing and calling frequencies and decreased their moving and feeding frequencies when exposed to red fox's feces and urine. 4) The increased red foxs feces and urine had no influence on the behavior of the pikas when the number of their natural enemies increased; the pikas obviously increased the observing frequencies and sharply decreased the calling frequency so as to decrease the direct predation risk. 5) There were no significantly behavioral differences between males and females as well as between adults and young. 6) The results reject the hypothesis l that the red fox's feces and urine as indirect predation risk suppresses the reproduction of the pikas and support the hypothesis 2 that the pikas can make decision by changing behavior to avoid the predation risk they encountered whenever.

10

Chaoborus flavicans in the food web - competitor or resource for fish?

Pekcan-Hekim Zeynep, Liljendahl-Nurminen Anne, Horppila Jukka

Polish Journal of Ecology

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2006

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Vol. 54, nr 4

701-707

EN

In lakes, chaoborids can be a food resource and also act as competitors for planktivorous fish. Usually their density varies reciprocally with the density of planktivorous fish, which forage on chaoborids. Results from Lake Hiidenvesi show, however, that in deep clay-turbid lakes chaoborids may be the main regulators of herbivorous zooplankton although the density of planktivorous fish is high. This is because turbidity reduces the feeding efficiency of fish while the feeding of chaoborids is not affected by the high turbidity levels.