scholarly journals Smålommens Gavia stellata häckningsframgång i artens svenska kärnområde

Ornis Svecica ◽  
2002 ◽  
Vol 12 (1–2) ◽  
pp. 1-33
Author(s):  
Börje Dahlén ◽  
Mats O G Eriksson
Keyword(s):  
Breeding Success ◽  
Large Scale ◽  
Annual Variation ◽  
Hatching Success ◽  
Coniferous Forests ◽  
Chick Survival ◽  
Freshwater Lakes ◽  
Early Start ◽  
Regional Factors

We investigated the breeding success of a Red-throated Diver Gavia stellata population of approximately 70 pairs during ten seasons, 1991–2000, in a 1820 km2 study area, dominated by coniferous forests and mires in Malung, Dalarna in Central Sweden. The majority of the pairs bred in tarns smaller than 1.0 ha and foraged in larger freshwater lakes or rivers up to a distance of 4.6 km. Average breeding success was 0.76 “large” chicks per pair and year, with a declining trend over the study period accompanied by a decline in the proportion of broods with two “large” chicks. Breeding success was higher in seasons with an average early start of incubation and could be related to higher hatching success and survival of chicks. Predation during incubation was probably an important reason for breeding failures, and abandoning or change of breeding tarns were related to breeding failures. The annual variation of the percentage of broods with two “large” chicks was synchronised between pairs foraging at different fishing lakes, which indicates the influence of some large-scale regional factors linked to the availability of food. Chick survival in two-chicks broods was significantly lower than in one-chick broods. The declining trend in breeding success is an incitement for future monitoring, and any link to impaired foraging conditions needs to be more closely addressed.

scholarly journals First data on breeding success of Croatian inland colonies of Common Tern Sterna hirundo

Acrocephalus ◽  
2019 ◽  
Vol 40 (180-181) ◽  
pp. 97-103
Author(s):  
Miloš Martinović ◽  
Jelena Kralj ◽  
Tomica Rubinić ◽  
Luka Jurinović ◽  
Ana Petrović ◽  
...  
Keyword(s):  
Clutch Size ◽  
Breeding Success ◽  
Hatching Success ◽  
Baseline Data ◽  
Common Tern ◽  
Sterna Hirundo ◽  
Chick Survival ◽  
Fledging Success ◽  
Artificial Lakes ◽  
Avian Pox

AbstractIn 2018 and 2019, the breeding success of two Common Tern colonies on artificial lakes near the River Sava in Zagreb, Croatia, was studied. The colonies were visited weekly from May to July and we collected data on phenology, number of breeding pairs, clutch size as well as egg and chick survival. We also conducted a comparison between early and late breeders. Hatching and fledging success was within previously observed ranges, apart from a low hatching success on Siromaja in 2019. The smaller colony on Siromaja had a higher productivity in both years than the colony on Rakitje, although in 2018 an avian pox virus killed much of the late chicks on Rakitje. Early breeders seem to have had higher hatching success and average clutch size. Furthermore, a greater proportion of them managed to hatch all their eggs compared to late breeders, but the differences were not statistically significant. Our study provided baseline data for future monitoring of phenology and breeding success with regard to the management of breeding colonies.

Ecological, coenotic and floristic analysis of groups of associations of broadleaved-coniferous forests from central European Russia

2001 ◽  
pp. 38-48 ◽  
Author(s):  
L. B. Zaugolnova ◽  
I. I. Istomina ◽  
E. V. Tikhonova
Keyword(s):  
Wide Distribution ◽  
European Russia ◽  
Coniferous Forests ◽  
Computer Data ◽  
East Europe ◽  
Central European ◽  
Reference Base ◽  
Floristic Analysis ◽  
Regional Factors

Two computer data bases were formed: reference base «Prodromus» including the nomenclature forest syntaxa and experienced geobotanic releves «Forests of European Russia». Ecological, coenotic and floristic analysis of broadleaved-coniferous forests mostly corresponding to association Rhodobryo rosei – Piceetum abietis Korotkov 1986 was conducted with these bases. Releves (305) from South taiga and broadleaved-coniferous subzone were used. The analysis revealed complex syntaxonomy, bo­real-nemoral character and wide distribution ass. Rhodobryo-Piceetum from central European Russia. Ecolo­gical comparison of this association with some no­men­clature types of broadleaved-coniferous communities in East Europe was carried out. Preliminary prodromus for Euro­pean Russian mixed forests is suggested. Role of ecologi­cal, succession and regional factors was shown for dif­ferentiation of syntaxa.

Human influences on breeding of south polar skuas in the eastern Larsemann Hills, Princess Elizabeth Land, East Antarctica

Polar Record ◽  
1996 ◽  
Vol 32 (180) ◽  
pp. 43-50 ◽  
Author(s):  
Z. Wang ◽  
F.I. Norman ◽  
J.S. Burgess ◽  
S.J. Ward ◽  
A.P. Spate ◽  
...  
Keyword(s):  
Breeding Success ◽  
Human Activities ◽  
Annual Variation ◽  
East Antarctica ◽  
Larsemann Hills ◽  
Catharacta Maccormicki ◽  
Area Development ◽  
South Polar ◽  
Made In ◽  
Area Data

AbstractBreeding activity of pairs of south polar skuas (Catharacta maccormicki) in the eastern Larsemann Hills, Princess Elizabeth Land, East Antarctica, was recorded in five of six austral summers between 1988 and 1994. More detailed observations of breeding success were made in the 1989/90 and 1993/94 summers. Although relatively few skuas nest in the study area, data suggest that there was inter-annual variation in numbers and locations of territories and chicks fledged. This variation is discussed in relation to increased human activities in the area (development of a summer base and more permanent stations) and to an enhanced access to human-derived foods. It is concluded that there has been some human impact on this species in the Larsemann Hills.

scholarly journals Subcolony Variation in Breeding Success in the Tufted Puffin (Fratercula Cirrhata): Association With Foraging Ecology and Implications

The Auk ◽  
2007 ◽  
Vol 124 (4) ◽  
pp. 1149-1157
Author(s):  
J. Mark Hipfner ◽  
Mathieu R. Charette ◽  
Gwylim S. Blackburn
Keyword(s):  
Stable Isotope ◽  
Breeding Success ◽  
Large Scale ◽  
Foraging Ecology ◽  
Isotope Analysis ◽  
Egg Yolk ◽  
Foraging Strategies ◽  
Small Scale ◽  
Carbon And Nitrogen ◽  
Tufted Puffin

Abstract Large-scale oceanographic processes are the main drivers of seabird breeding success, but small-scale processes, though not as well understood, can also be important. We compared the success of Tufted Puffins (Fratercula cirrhata) breeding at two subcolonies only 1.5 km apart on Triangle Island, British Columbia, Canada, 2002–2005. In addition, we used stable-isotope analysis to test the hypothesis that parental foraging strategies differed between the two subcolonies, potentially underlying the variation in breeding success. Success was concordant across years at the two sites but, overall, Tufted Puffins bred more successfully at Strata Rock than at Puffin Rock. They raised chicks in all four years at Strata Rock, but in only three years at Puffin Rock; in two of those three years, Strata Rock chicks were, on average, 60 g and 100 g heavier than Puffin Rock chicks just before fledging. Discriminant analysis of carbon and nitrogen stable-isotope ratios in egg yolk and chick blood in 2004 and 2005 indicated that parental foraging differed between the two subcolonies, with both spatial (δ13C) and trophic-level (δ15N) differences involved. Thus, our study demonstrates the existence of foraging asymmetries in a pelagic seabird at a small spatial scale (between subcolonies), complementing patterns found at larger scales (between colonies). Moreover, the foraging asymmetries were associated with inequalities in fitness measures. We conclude that small-scale processes—in this case, systematic differences in the foraging ecology of local groups—can interact with large-scale oceanographic processes to determine seabird breeding success. Variation sous-coloniale du succès de reproduction de Fratercula cirrhata: Association avec l'écologie de la quête alimentaire et implications

scholarly journals Does the vicinity of the Black-Headed Gull colony (Chroicocephalus ridibundus) increase the breeding success of the Common Tern (Sterna hirundo) on the islands of the middle Vistula?

2018 ◽  
Vol 16 (4) ◽  
pp. 43-50
Author(s):  
Dariusz Bukackiński ◽  
Monika Bukacińska ◽  
Milena Grabowska
Keyword(s):  
Hatching Success ◽  
Single Species ◽  
Common Tern ◽  
Egg Mass ◽  
Chick Survival ◽  
Effective Protection ◽  
Vistula River ◽  
Nesting Site ◽  
The Common ◽  
The City

We conducted our study in the Common Tern colony (STH) located on an island in the middle Vistula River course, at the height of the city of Dęblin (km 393–394 of the waterway), in 2017. Our goal was to investigate some aspects of the biology and reproductive ecology of this species. Due to the fact that STH breeds both in single-species as well as in two- or multi-species colonies, in associations with Little Terns (Sternula albifrons), Black-Headed Gulls (Chroicocephalus ridibundus) (LAR) and/or Mew Gulls (Larus canus), we wanted to investigate whether the neighborhood of other species (in this case LAR) affected hatching success and chick survival in STH. Our results clearly show that the presence of breeding terns in the neighborhood of the LAR colony was not accidental and/or caused by the lack of space on the island and/or the possibility of nesting elsewhere. The height of nesting site, type of nesting habitat, clutch size, mean egg volume and mean egg mass of these STH pairs did not differ significantly from those that formed a single species colony, on the same island but several hundred meters away. However, STH nests in the neighborhood of the LAR colony were established much earlier and both the hatching success and chick survival of STH during the early-chick stage were twice as high. Thus, we can conclude that the LAR colony could provide an effective protection against predation of crows, magpies and gulls, dangers which accounted for the vast majority of STH nest failures in the year of our study.

Thermal heterogeneity along a braided floodplain river (Tagliamento River, northeastern Italy)

2001 ◽  
Vol 58 (12) ◽  
pp. 2359-2373 ◽  
Author(s):  
David B Arscott ◽  
Klement Tockner ◽  
J V Ward
Keyword(s):  
Large Scale ◽  
Regression Analyses ◽  
Thermal Variation ◽  
Heating And Cooling ◽  
Northeastern Italy ◽  
Tagliamento River ◽  
Regional Factors ◽  
Thermal Patterns ◽  
Thermal Heterogeneity ◽  
Degree Slope

Daily and seasonal water temperature patterns were investigated at 22 habitats in five geomorphic reaches along an Alpine-Mediterranean river. Study reaches spanned 2nd- to 7th-order river segments. Habitats included headwater streams, main and secondary channels, backwaters, and isolated pools. Multiple linear regression analyses extracted elevation and azimuth (aspect) out of eight geographical and environmental variables to explain average daily temperature patterns among habitats. Azimuth and, to a lesser degree, slope, depth, velocity, and canopy were primary determinants of diel temperature amplitude and maximum rates of diel heating and cooling. Within lowland floodplain reaches, the relative influence of groundwater and surface water varied substantially among habitats. Thermal variation among habitats was greatest in lowland floodplain reaches (nearly 15°C difference). In summer and autumn, variation between lowland floodplain aquatic habitats exceeded thermal variation observed in the main channel along the entire river corridor (120 km; 5–1100 m above sea level). Spatiotemporal variation in temperature was greatest in lower reaches owing to the interaction of water level and connectivity of isolated water bodies. Influence of groundwater and cool-water tributaries exemplified the importance of local factors (geomorphology and hydrology) superimposed on regional factors (climate and altitude) in determining large-scale thermal patterns.

The effect of an indirect anthelmintic treatment on parasites and breeding success of free-living pheasantsPhasianus colchicus

2006 ◽  
Vol 80 (4) ◽  
pp. 409-415 ◽  
Author(s):  
R.A.H. Draycott ◽  
M.I.A. Woodburn ◽  
D.E. Ling ◽  
R.B. Sage
Keyword(s):  
Breeding Success ◽  
Large Scale ◽  
Parasite Burden ◽  
Anthelmintic Treatment ◽  
Phasianus Colchicus ◽  
Free Living ◽  
Parasitic Worm ◽  
Large Scale Field ◽  
Syngamus Trachea

AbstractIn Great Britain free-living common pheasantsPhasianus colchicusare often managed at high densities owing to their popularity as a quarry species. They are prone to infection by a range of parasite species includingHeterakis gallinarum,Capillariaspp. andSyngamus trachea. In 1995 the efficacy of an indirect anthelmintic technique for controlling parasitic worm burdens of pheasants was determined in a pilot study on a shooting estate in the south of England. Between 2000 and 2003 a large-scale field experiment was conducted on nine estates in eastern England to determine the effect of the technique on parasite burden and pheasant breeding success. In the absence of anthelmintic treatment worm burdens increased rapidly through March and April, whereas birds given anthelmintic-treated grain had lower worm burdens during the same period. The breeding success of pheasants was significantly higher on plots provided with anthelmintic treatment, although no long-term increases in population densities were observed. The burdens of the most common parasiteH. gallinarumwere significantly lower in pheasants from treatment plots six weeks after the anthelmintic treatment had ceased, but spring treatment did not influence parasite burden in the following winter.

Sign in / Sign up

Export Citation Format

Share Document