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1

Seasonal movements of wisents (Bison bonasus L., 1758) in the Bieszczady Mountains (SE Poland)

100%
Pierzanowski K., Januszczak M., Woloszyn-Galeza A.
Biological Letters
|
2012
|
tom 49
|
nr 1
2

First record of seasonal over sea migration of Miniopterus schreibersii and Myotis capaccinii between Balearic Islands (Spain)

100%
Amengual B., Lopez-Roig M., Serra-Cobo J.
Acta Chiropterologica
|
2007
|
tom 09
|
nr 1
3

Effect of the bird cherry-oat aphid Rhopalosiphum padi L. feeding on phytochemical responses within the bird cherry Prunus padus L.

100%
Sytykiewicz H., Golawska S., Chrzanowski G.
Polish Journal of Ecology
|
2011
|
tom 59
|
nr 2
Host specialization plays a central role in physiological diversification of aphids and plant-insect co-evolution. Different morphs of the bird cherry-oat aphid (Rhopalosiphum padi L.) are specialized and locally adapted to both primary and secondary hosts. The abundance of bird cherry-oat aphid population was estimated using the technique of direct counting of aphid individuals infesting 50 randomly selected, fully expanded 1-year side shoots of bird cherry (approx. 40 cm long) grown in the Municipal Park „Aleksanria” in Siedlce (central-eastern Poland). Entomological observations were conducted during three consecutive vegetation seasons: 2001–2003. The impact of R. padi feeding on composition of free amino acids within leaves of its primary host (the bird cherry, Prunus padus L.), infested and uninfested by aphids were studied. Eight essential amino acids (Val, Thr, Phe, Ileu, Leu, Met, His and Lys) and seven non-essential amino acids (Asp, Glu, Pro, Ser, Ala, Gly and Tyr) were identified in the bird cherry-oat leaves with the use of highperformance liquid chromatography (HPLC) separation. There were quantitative differences in free amino acids content between the tested bird cherry-oat leaves (infested and uninfested by aphids). Levels of the free amino acids were decreased in leaves attacked by R. padi, and detailed analyses revealed about 20% decline in the content of studied components during maximal aphid abundance in comparison with non-infested leaves. Additionally, the feeding behavior of the bird cherry-oat aphid seasonal morphs (fundatrix, fundatrigeniae, alatae) on the primary host was investigated. Using the electrical penetration graph (EPG) we showed differences in feeding behavior of bird cherry-oat aphid morphs on primary host. The total probing time was greatest for fundatrigeniae among all studied morphs. These individuals spent more time during phloem sap ingestion then others. Adults of alatae were not active in the phloem sap ingestion on the bird cherry. Among the tested morphs xylem sap ingestion activity was greatest for alatae. It is hypothesized that rejection of primary host and subsequent the bird cherry-oat aphid migration onto secondary hosts may be stimulated by the decline in levels of free amino acids within primary host leaves caused by long-term R. padi feeding. Comparative analyses of the aphid probing behavior additionally proved that P. padus leaves possessed high nutritive value of food for non-winged morphs (early stages of aphid infestation), while not sufficient for winged alatae (terminal phase of infestation).
4

Dates of migration waves - a coincidence or an effect of biologically based mechanism? Improvement of the method of analysing the seasonal migration dynamics

100%
Kopiec-Mokwa K.
The Ring
|
1999
|
tom 21
|
nr 2
5

Evaluation of maternal features as indicators of asynchronous embryonic development in Miniopterus natalensis

80%
Mason M. K., Hockman D., Jacobs D. S., Illing N.
Acta Chiropterologica
|
2010
|
tom 12
|
nr 1
The timing of early reproductive events for the Natal long-fingered bat, Miniopterus natalensis, was examined during its breeding season (August to December) in its maternity roost at the De Hoop Nature Reserve (South Africa). This migrating species is monoestrous with copulation occurring around April in South African populations. Embryonic development is stalled during hibernation by delayed implantation of the blastocyst. As a result, limb bud stage embryos (CS13) are first noted in other South African populations in mid-September. The timing of these reproductive events for the De Hoop population is similar with bats arriving at the maternity roosts in September and embryos at the limb bud stage (CS13) being noted in this month. Pregnancy was not synchronous in the population with bats dissected on the same day exhibiting differences in the stage of development of their young (CS11 to CS21 being the largest range). Maternal features (progesterone concentration, body mass and abdominal distension) were analysed to determine if they provided a reliable estimate of embryonic stage. The progesterone concentrations of pregnant bats showed a similar profile to the Kwa-Zulu Natal and the Eastern Cape populations. Though progesterone concentration did increase as pregnancy progressed, it was not an accurate predictor of embryonic stage. Maternal body mass did not correlate with the stage of embryonic development. However, abdominal distension determined by palpation is an accurate field based predictor of the stages of pregnancy: no abdominal distension, small to medium abdominal distension and large abdominal distension distinguished between non-pregnant bats and those carrying either early (CS11–CS15) or mid-developmental stages (CS16–CS21), respectively.
6

Age and growth of the golden grey mullet Liza aurata (Actinopterygii: Mugiliformes: Mugilidae), in the Messolonghi-Etoliko Lagoon and the adjacent Gulf of Patraikos, Western Greece

80%
Hotos G. N., Katselis G. N.
Acta Ichthyologica et Piscatoria
|
2011
|
tom 41
|
nr 3
Background. The fisheries of the Greek lagoons is based on the seasonal fish migration from coastal areas to the lagoon and the summer-to-winter offshore fish migration. The knowledge of the age and growth of the species in the two connected regions is essential for the proper management of the resources. The aim of this study was to estimate the age and growth of Liza aurata in the Messolonghi-Etoliko Lagoon system and the neighbouring coastal waters of the Gulf of Patraikos (Western Greece). Materials and methods. From December 1992 to February 1994, a total of 1146 individuals of Liza aurata were caught in the Klisova Lagoon (part of the lagoon complex of Messolonghi-Etoliko) and their adjacent sea coastal area, using barrier fish traps, seine, and trammel nets. The fish age was determined from scale readings. Back calculated lengths at age, as derived using scales readings, were used to estimate the growth parameters of von Bertalanffy equation. The length–weight relation was estimated by the equation: W = a · Lb. Results. The total length (L) of examined specimens ranged from 9.7 to 59 cm. The scale readings revealed nine age classes in the Gulf of Patraikos (0 to VIII) and seven (0 to VI) in the lagoon. Maximum age was found to be 8 and 6 years for females and males, respectively. The analysis of the residuals sum of squares showed that the VBGF curves of sexes between the Patraikos sea area and the lagoon were not significantly different (sexes: F = 0.51, P > 0.05 and regions: F = 0.46, P > 0.05, respectively). The estimated values of VBGF for all samples were L∞ = 65.08 ± 2.61 cm; k = 0.149 ± 0.017 year–1 and t0 = –1.15 ± 0.063 year. No significant difference on the length–weight relations among the sexes was found (F = 3.15, P > 0.05) while a significant difference on the length–weight relations among the regions (sea: W = 0.0036L3.26; lagoon: W = 0.0057L3.13) was found (F = 21.1, P < 0.05) which reproduced a rather low difference (<±5%) along the size (weight) of species. The length–weight relations exhibited allometry. Conclusion. The age and growth in length and weight of Liza aurata in the lagoon system of Messolonghi-Etoliko and the neighbouring seawaters of Gulf of Patraikos were not significantly different. This could be explained by the fact that the relative high salinity situation of the lagoon may rebut their high trophic advantage for the fish and/or alternatively, by a scenario that is based on the seasonal migrations of species between sea and lagoon.
7

Burullus ringing station (N Egypt) - ringing results and seasonal bird migration dynamics in 2005-2007

80%
Zaniewicz G., Chrusciel J.
The Ring
|
2011
|
tom 33
|
nr 1-2
8

Sezonowa aktywnosc lotow mszyc w odlowach aspiratorem Johnsona w latach 1998-2001

80%
Zlotkowski J.
Progress in Plant Protection
|
2002
|
tom 42
|
nr 2
712-715
9

Relict invertebrates in lacustrine habitats: life history of Pallaseopsis quadrispinosa [Sars, 1867] [Amphipoda: Gammaridae] in a deep mesotrophic lake

80%
Kolodziejczyk A., Niedomagala W.
Polish Journal of Ecology
|
2009
|
tom 57
|
nr 4
729-740
Three crustacean species of postglacial origin are found in lakes of northern Poland. One of them is Pallaseopsis quadrispinosa which inhabits deep, oligotrophic and mesotrophic lakes. The deepest lake in Poland (area 3.11 km², max. depth 108.5 m) and on the entire Central European Plain is Lake Hańcza, an α-mesotrophic lake of unique character. A study of P. quadrispinosa in this lake was carried out between AprilOctober in 2000. Samples were collected at ten sites, to a depth of 16 m, using a tow net. In April, this amphipod crustacean was observed at depths of between 1–12 m with maximal density at 4–6 m (800 individuals per 100 m²). In May and July/ August, the density was reduced and this organism was found mainly between 6–12 m. In October, P. quadrispinosa was distributed between 1–6 m, with a maximal density of 1400 individuals per 100 m² at 2–4 m. Seasonal changes in density at various depths and the spatial heterogeneity of the occurrence of this amphipod indicate migration, probably related to changes in the water temperature and the reproductive cycle. Breeding of P. quadrispinosa was observed throughout the study period, with reproductive peaks in the early spring and autumn. The average number of eggs carried by ovigerous females ranged from 12 to 64, and was significantly correlated with the size of the individual. Newborn juveniles were spatially isolated from the adults as they tended to accumulate at the shallower bottom depth. The sampled material revealed the presence of two subpopulations of P. quadrispinosa. Environmental conditions, especially the consistently high level of dissolved oxygen, reproduction, apparently long life-span and occurrence in all parts of the lake indicate that the P. quadrispinosa population in Lake Hańcza is stable and in good condition.
10

Migration patterns of acoustic scatterers in the southern Baltic Sea

80%
Szczucka J., Klusek Z.
Oceanologia
|
1996
|
tom 38
|
nr 1
11

Comparability of wing length measurements based on data collected at two twin stations during migration

61%
Zaniewicz G.
The Ring
|
2012
|
tom 34
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