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Breeding Ecology of the Iberian Chiffchaff Phylloscopus ibericus : First Data from North Africa

Bougaham Abdelazize Franck

Polish Journal of Ecology

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2021

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Vol. 69, nr 1

51--56

EN

Till now, the breeding biology of several North African bird populations has been little studied, particularly that of the southern populations of Iberian chiffchaff Phylloscopus ibericus. In the present study, total of 31 nests of Iberian chiffchaff were monitored in the northeastern Algeria during 2013-2017. The nesting period, clutch and brood sizes, and reproductive success of the species were determined. The first egg-laying dates of the first broods were spread over the first twenty days of April. There were significant among-year variations in nesting seasons. The Iberian chiffchaff clutch sizes averaged 4.51 eggs. The number of hatchlings and fledglings averaged 4.09 and 3.54 nestlings, respectively. There is no correlation between the nest height above the ground and the hatching and the breeding success of the species. Predation and nest abandonment were the main causes of the breeding failure of the Iberian chiffchaff in studied population, however, in general the breeding success was high – 80.7%. Breeding data for the Iberian chiffchaff at the southern edge of its breeding range in North Africa show smaller clutches and production of fewer young compared to the common chiffchaff Phylloscopus collybita in Europe.

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A one-pass heuristic for nesting problems

Kierkosz Igor, Łuczak Maciej

Operations Research and Decisions

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2019

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Vol. 29, No. 1

37--60

EN

A two-dimensional cutting (packing) problem with items of irregular shape and rectangular sheets is studied. Three types of problems are considered: single-sheet problems without restrictions on the number of elements, single-sheet problems with restrictions on the number of elements, and cutting stock problems (restricted number of items and unrestricted number of sheets). The aim of the optimization is to maximize the total area of the elements cut from a single plate or to minimize the number of sheets used in cutting. A one-pass algorithm is proposed which uses the popular concept of a no-fit polygon (NFP). The decision on whether an item is cut from a sheet in a given step depends on the value of a fitting function. The fitting function depends on the change in the NFP of individual items. We test eight different criteria for the evaluation of partial solutions. On the basis of numerical experiments, the algorithm that generates the best solution for each of the considered problem types is selected. The calculation results for these algorithms are compared with results obtained by other authors.

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Effect of parental care on depredation of Blackcap Sylvia atricapilla L. nests: an experiment with artificial clutches

Zieliński J., Lik M.

Polish Journal of Ecology

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2014

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Vol. 62, nr 4

761--769

EN

Small solitary open nesting passerines, such is the Blackcap Sylvia atricapilla that builds nest in the undergrowth, have little chance of successfully scaring off a predator to defend a nest. The aim of our study was to determine if parental care by Blackcaps can reduce the risk of depredation of its nests. We compared the survival of natural clutches with artificial clutches (plasticine and independently both plasticine & quail eggs). The artificial clutch was placed in a nest after the natural clutch had been concluded, and the results were analysed as matched pairs of data. We assumed that significantly higher survival rates of natural clutches than of artificial clutches deprived of parental care, might indicate a significant positive effect of parental care on reducing depredation risk of Blackcap clutches. Losses caused by birds, rodents and larger mammals were 49%, 41% and 9%, respectively. The differences in survival rates of artificial clutches (plasticine as well as quail & plasticine) and natural clutches were not statistically significant. This might show that parental care is not strong enough to significantly reduce depredation risk of Blackcap clutches. Although this conclusion should be treated cautiously because it was difficult to assess the influence of using artificial clutches on our results.

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The effect of Grey Heron (Ardea cinerea L.) colony on the surrounding vegetation and the biometrical features of three undergrowth species

Żółkoś K., Meissner W.

Polish Journal of Ecology

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2008

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Vol. 56, nr 1

65-74

EN

Bird breeding colonies are known to influence the habitats and phytocoenoses they occupy in different ways. Most papers concern long-lasting colonies, in which floristic composition of phytocoenoses have been already altered largely. This research was aimed to estimate the changes in the floristic composition of the forest phytocoenosis after three years of the existence of the Grey Heron (Ardea cinerea L.) breeding colony as well as to examine the influence of nutrient enrichment on the size and shape of leaves and inflorescences of three plant species Rumex acetosella L., Anthoxanthum odoratum L. and Moehringia trinervia (L.) Clairv., which have different habitat requirements. The number of vascular plant species within the colony area (0.4 ha) increased almost double and appearance of new, mostly nitrophilous, taxa like Sambucus racemosa L., Galeopsis pubescens Besser and Stellana media (L.) Vill. were observed. The vertical structure of phytocoenosis has also changed. The undergrowth appeared and dense moss layer was mostly eliminated. In case of all investigated species, the enlargement of leaf surface was found. The greatest relative increase concerned leaf width of Moehringia trinervia and Rumex acetosella - 67 and 73%, respectively. The leaf blade of Anthoxanthum odoratum increased largely in length (99%). The enlargement of the surface of assimilative apparatus was not only due to the increase of linear dimensions, but also to rounding of the leaf blade. This was not observed in case of Rumex acetosella which is characterized by elongated, lanceolate leaf blade. Differences observed among the species are probably due to differentiated leaf blade structure. Only Moehringia trinervia can be found in well-established Grey Heron colonies, while Rumex acetosella and Anthoxanthum odoratum are known to be suppressed by heavy input of nitrogen fertilizer. Thus, it seems that after few years of benefits at least Rumex acetosella and Anthoxanthum odoratum withdraw from the area altered by Grey Heron colony, because the change in root absorption and capacity in highly fertile habitat leads to toxic accumulation of nutrients.

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Predation survival of ground nesting birds in grass and wheat fields: experiment with plasticine eggs and artificial nests

Purger J., Csuka S., Kurucz K.

Polish Journal of Ecology

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2008

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Vol. 56, nr 3

481-486

EN

There are no agricultural activities in Hungarian energy grass plantations (Elymus elongatus (Host) Runemark before harvesting in August, so the breeding success of the ground-nesting Common pheasant (Phasianus colchicus L.) and Common quail (Coturnix coturnix (L.)) is probably higher than in the neighbouring intensively managed grain fields. The dominant nest predators of these bird species (e.g. Red fox Vulpes vulpes L.) prey mostly on small mammals, thus the abundance of small mammals can influence the survival rates of ground-nesting birds. These assumptions were tested using artificial ground-nests and small mammal live traps in late May 2005. Of the nests, 25 were placed in the energy grass field which covered 60 ha and another 25 in the wheat field which area was 20 ha. Each of the nests contained one chicken egg, one quail egg and one plasticine dummy-egg. Real eggs were placed for the evaluation of nest predation rates and artificial plasticine eggs for predator identification from tooth and bill imprints. Following the placement of artificial nests, they were checked repeatedly between 16.00 and 18.00 every day. In both plots, 25 traps were set up, baited for 4 nights with quail egg and for another 4 nights with plasticine egg. Artificial nests lasted for 3 days in the wheat field and for 4 days in the energy grass field. The major predators in wheat were birds (16%) and mammals (84%), whereas in energy grass all predation (100%) was caused by mammals. There was no significant difference between types of predators in the two habitats. On-spot observations, traces and marks left on plasticine eggs, several droppings and the patterns of nest predation all suggested that the majority of nests were destroyed by Red fox. A significantly higher proportion of plasticine eggs were damaged in wheat (80%) than in energy grass (48%). Based on marks left on plasticine eggs, small mammal abundance was higher in wheat (80%) than in energy grass (33%), the latter habitat not yielding any small mammal captures at all. Traps in the wheat field caught significantly more small mammals with plasticine eggs (14) than with quail eggs (5). Plasticine eggs had greater attraction effect on small mammals, thus could negatively influence experiments with artificial ground nests.

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Effect of old nest material in nestboxes on ectoparasites abundance and reproductive output in the European Starling (Sturnus vulgaris L.)

Mazgajski T.

Polish Journal of Ecology

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2007

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Vol. 55, nr 2

377-385

EN

Before breeding, hole nesting birds face the problem of the presence of old nest material from previous seasons in their nest sites. This material fills the cavity, making it shallower, resulting in greater brood vulnerability to predators, as well as creating good conditions for ectoparasite development. As a consequence, this may negatively affect many breeding parameters of hole nesters. However, adult birds may compensate the effect of blood sucking ectoparasites by increasing their feeding rates. It is known that the European Starling Sturnus vulgaris L. can deepen its nest site by removing old nest material. Therefore, a study was conducted to find out whether the presence of old nest material influences ectoparasite abundance in newly built nests, reproductive parameters, as well as nestling. body parameters and feeding rates in this species. An experiment with nestboxes was carried out in two forested areas. Two groups of nestboxes were prepared - one contained old nests from the previous breeding season, and the other group was cleaned with old nests removed. During the breeding season, data on Starling reproduction were collected, i.e. laying dates, clutch size and number of fledglings. Nestling body parameters were measured on the 6th, 9th, 13th and 17th days of their lives. On the 10th and 15th days of nestling life, the number of feedings was counted over a period of 30 minutes. Nests were collected and analyzed for the presence of ectoparasites. It was found that the average number of ectoparasites, both fleas and mites, was greater in nests built on old nest material, and that this number was highly correlated. In further analysis, two possible effects on reproductive output were investigated separately: the presence of old nest material and the abundance of ectoparasites. Clutch size and number of fledglings were smaller in broods from nestboxes containing old nest material, but there was no such relationship to laying dates and nestlings. body parameters (weight, tarsus and wing length). The number of feeding trips on the 10th day of nestling life was higher in .cleaned. nestboxes, but a similar level was achieved by the 15th day in both groups of nestboxes. It was found that ectoparasite abundance did not influence any of the studied parameters of Starling reproduction, i.e. breeding, nestlings. physical condition or number of feedings. This confirmed earlier findings that ectoparasite infestation at a natural level does not affect Starlings. breeding. It seems that the negative effect of the presence of old nest material in nest sites is connected to the costs of site preparation and old nest material removal, which are borne by the females.

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Deos the Red-backed Shrike (Lanius collurio L.) benefit from nesting in the association with the Barred Warbler (Sylvia nisoria Bechst.)?

Goławski A.

Polish Journal of Ecology

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2007

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Vol. 55, nr 3

601-604

EN

The co-occurrence of Redbacked Shrikes (Lanius collurio) and Barred Warblers (Sylvia nisoria) was monitored during the years 1999-2003 at 343 ha of agricultural landscape of eastern Poland. Each year 25-31 pairs of Red-backed Shrikes and 3-8 pairs of Barred Warblers were nesting. In total, during five seasons, shrikes were nesting in the vicinity (within 50 m from the centre of the Barred Warbler territory) of 22 out of 24 (92%) warbler territories. The breeding success of the pairs nesting close to Barred Warbler territories was 89%, as compared with 61% for the remaining pairs and it was statistically significant. No difference was found in the clutch size between Redbacked Shrikes nesting close to Barred Warblers and far from them, but statistically significant difference was found in numbers of fledglings between them. The present results imply that close nesting of these two species reduces the risk of nest predation. This may be due to the aggression of Barrred Warblers towards potential predators, as this species actively attacks predators near the nest.

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Density, distribution and nest-sites of woodpeckers (Picidae) in a managed forest of Western Polan

Kosiński Z., Kempa M.

Polish Journal of Ecology

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2007

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Vol. 55, nr 3

519-533

EN

Abundance, distribution and nest-site characteristics of woodpecker species (family Picidae), i.e., Great Spotted Woodpecker (Dendrocopos major L.), Middle Spotted Woodpecker (D. medius L.), Lesser Spotted Woodpecker (D. minor L.), Black Woodpecker (Dryocopus martius L.), Grey-faced Woodpecker (Picus canus Gmel.) and Wryneck (Jynx torquilla L.), coexisting in managed forest are described. All species preferred old deciduous forest stands ([is greater than or equal to] 81 years old) as nest-sites, however, they differed in most aspects of nest site selection. Great- and Middle Spotted Woodpeckers excavated nest-holes most commonly in oaks (78 and 86% of nests, respectively), but Black- and Grey-faced Woodpeckers in beeches (71 and 100% of nests). However, placement of nest-holes within the same tree species differed among woodpecker species. Great Spotted- and Grey-faced Woodpeckers nested three meters lower (9 m) compared to Middle Spotted and Black Woodpeckers (12 m). Lesser Spotted- Woodpeckers excavated breeding holes relatively the highest in respect to tree height. With the exception of Lesser Spotted Woodpeckers, all specie used live trees as nest sites. Weaker excavators such as Middle Spotted- and Lesser Spotted Woodpeckers, nested more frequently in limbs and branches (31 and 25% of nests, respectively) compared to strong excavators, i.e., Great Spotted-, Black- and Greyfaced Woodpeckers (<8% of nests in limbs or branches). Weaker excavators more frequently selected dead tree fragments compared to strong excavators.