scholarly journals Breeding success and breeding population trends of waterfowl: implications for monitoring

2011 ◽  
Vol 17 (3) ◽  
pp. 225-239 ◽  
Author(s):  
Mia Rönkä ◽  
Lennart Saari ◽  
Martti Hario ◽  
Jari Hänninen ◽  
Esa Lehikoinen
Keyword(s):  
Breeding Success ◽  
Breeding Population ◽  
Population Trends

scholarly journals Variation among colonies in breeding success and population trajectories of wandering albatrosses Diomedea exulans at South Georgia

Polar Biology ◽  
2021 ◽  
Author(s):  
Carola Rackete ◽  
Sally Poncet ◽  
Stephanie D. Good ◽  
Richard A. Phillips ◽  
Ken Passfield ◽  
...  
Keyword(s):  
Body Condition ◽  
Breeding Success ◽  
Population Trends ◽  
Contributing Factors ◽  
South Georgia ◽  
Vortex Model ◽  
Demographic Rates ◽  
Diomedea Exulans ◽  
Adult Body ◽  
Provisioning Rate

AbstractThe wandering albatross, Diomedea exulans, is a globally threatened species breeding at a number of sites within the Southern Ocean. Across the South Georgia archipelago, there are differences in population trends even at closely located colonies. Between 1999 and 2018 the largest colony, at Bird Island, declined at 3.01% per annum, while in the Bay of Isles, the decline was 1.44% per annum. Using mean demographic rates from a 31-year study at Bird Island and an 11-year study of breeding success at Prion Island in the Bay of Isles in a VORTEX model, we show that differences in breeding success do not fully explain observed differences in population trends. Other potential contributing factors are differential use of foraging areas, with possible knock-on effects on adult body condition, provisioning rate and breeding success, or on bycatch rates of adults or immatures.

Black-Faced Spoonbill Platalea minor Population Trends, Breeding Success, and Nest Characteristics in the Chilsan Archipelago, South Korea

2021 ◽  
Vol 20 (1) ◽  
Author(s):  
Seok-Jun Son ◽  
Ki-Sup Lee ◽  
In-Ki Kwon ◽  
Jung-Hoon Kang ◽  
Sung-Kyung Lee ◽  
...  
Keyword(s):  
South Korea ◽  
Breeding Success ◽  
Population Trends ◽  
Minor Population

scholarly journals Long-term population trends of the Red-legged CormorantPhalacrocorax gaimardion the Argentine coast

2014 ◽  
Vol 25 (2) ◽  
pp. 234-241 ◽  
Author(s):  
ANA MILLONES ◽  
PATRICIA GANDINI ◽  
ESTEBAN FRERE
Keyword(s):  
Population Change ◽  
Breeding Population ◽  
Temporal Variations ◽  
Population Trends ◽  
World Population ◽  
Ocean Productivity ◽  
Marine Primary Productivity ◽  
Long Term Trend ◽  
Positive Effect

SummaryThe world population of Red-legged CormorantPhalacrocorax gaimardiis reasonably small and has showed rapid declines. In Argentina, this species breeds in 13 localities and is considered as ‘Endangered’ by the national government. In this study, we provide information about population trends of the Red-legged Cormorant on the Argentine coast, between 1990 and 2009. We also discuss whether these trends could be related to sea surface temperature and marine primary productivity, both of which are considered oceanographic factors that can affect breeding seabirds. The long-term trend in the breeding population showed a slight decrease of 1.2% per year. Seven colonies showed an average population change < 1. Periods of stability and increase were identified over the study period, but they were insufficient to compensate for the decreases. The largest colony of Red-legged Cormorants (La Mina, with more than 55% of the entire breeding population) seems to determine the overall population trend. We did not find a direct relationship between the overall number of Red-legged Cormorants and the two oceanographic factors analysed. However, our analysis detected a positive effect of ocean productivity close to the coast on the largest colony at the beginning of the breeding season, suggesting that coastal ocean productivity could be an important factor affecting temporal variations in the Argentinian population.

Using stable isotopes to link breeding population trends to winter ecology in Willow Warblers,Phylloscopus trochilus

Bird Study ◽  
2013 ◽  
Vol 60 (2) ◽  
pp. 211-220 ◽  
Author(s):  
Catriona A. Morrison ◽  
Robert A. Robinson ◽  
Jacquie A. Clark ◽  
Alina D. Marca ◽  
Jason Newton ◽  
...  
Keyword(s):  
Stable Isotopes ◽  
Breeding Population ◽  
Population Trends ◽  
Winter Ecology ◽  
Phylloscopus Trochilus

Breeding success and population trends in Adélie penguins in areas with low and high levels of human disturbance

Polar Biology ◽  
2007 ◽  
Vol 30 (7) ◽  
pp. 917-924 ◽  
Author(s):  
A. R. Carlini ◽  
N. R. Coria ◽  
M. M. Santos ◽  
M. M. Libertelli ◽  
G. Donini
Keyword(s):  
Breeding Success ◽  
Human Disturbance ◽  
Population Trends ◽  
Adélie Penguins

A population decline in Weddell seals: real or sampling artefact?

1992 ◽  
Vol 19 (1) ◽  
pp. 59 ◽  
Author(s):  
K Green ◽  
V Wong ◽  
HR Burton
Keyword(s):  
Food Availability ◽  
Population Decline ◽  
Breeding Population ◽  
Population Trends ◽  
Weddell Seals ◽  
Population Sizes

Aerial counts of Weddell seals during the moult did not provide a useful index of population trends. Seals may spent longer foraging in the water in some years than in others (possibly because of changes in food availability), with the result that differing proportions of the population are counted in different years. It is concluded that little can be inferred about interannual differences in population sizes without reference to the size of the breeding population.

scholarly journals Population status, breeding biology and conservation of the Tristan Albatross Diomedea [exulans] dabbenena

2001 ◽  
Vol 11 (1) ◽  
pp. 35-48 ◽  
Author(s):  
PETER G. RYAN ◽  
JOHN COOPER ◽  
JAMES P. GLASS
Keyword(s):  
Breeding Success ◽  
Breeding Population ◽  
The Past ◽  
Population Decrease ◽  
Diomedea Exulans ◽  
Large Colony ◽  
Gough Island ◽  
Incomplete Coverage ◽  
Complete Survey ◽  
Central South

Tristan Albatross Diomedea [exulans] dabbenena is the most genetically distinct of the five taxa that form the Wan dering Albatross superspecies, and has been listed as Endangered. It breeds only on Gough and Inaccessible Islands in the Tristan da Cunha group, central South Atlantic Ocean. The entire breeding population was surveyed during 1999-2000. A mid-September survey at Gough Island recorded 1,129 chicks, equivalent to an annual breeding effort by approximately 1,500 pairs. Only one chick was present at Inaccessible Island in 1999, and another pair laid an egg in 2000. The annual breeding effort at this island has not exceeded three pairs since the 1950s. None were found during an incomplete survey at Tristan, where the species bred in the past, but birds were seen flying over the island. A complete survey and attempts to promote recolonization of Tristan are warranted. Breeding success at Gough Island averaged 63%, and no birds that bred successfully attempted to breed the following year. Breeding success was greater and less variable in a large colony at Gonydale than at a peripheral colony at Tafelkop. Young birds returned to the island after 3-4 years (4-5 years old), and the modal age of first breeding was 8 years, with some individuals breeding as young as 6 years. Most chicks (81%) recruited to their natal colony, but some recruited to colonies up to 3 km from their natal site. Among adults, fidelity to partners and breeding colony was high. Of nine birds recovered away from the island, at least four were killed by longline fishing. Despite its known mortality on longlines, the Gough Island census exceeded demipopulation estimates from the 1970s and early 1980s, possibly due to incomplete coverage by previous surveys and a poor breeding season in 1998. Given the lack of evidence for a population decrease, Tristan Albatross should be listed as Vulnerable. It is the third rarest albatross species, however, and its population size warrants monitoring. We provide guidelines for repeatable censuses at Gough Island.

scholarly journals Population dynamics of the White Stork Ciconia ciconia in Slovenia between 1999 and 2010

Acrocephalus ◽  
2010 ◽  
Vol 31 (145-146) ◽  
pp. 101-114 ◽  
Author(s):  
Damijan Denac
Keyword(s):  
Population Dynamics ◽  
Breeding Success ◽  
Weather Conditions ◽  
Breeding Population ◽  
White Stork ◽  
Breeding Period ◽  
Ciconia Ciconia ◽  
White Storks ◽  
Breeding Grounds ◽  
Unfavourable Weather

Population dynamics of the White StorkCiconia ciconiain Slovenia between 1999 and 2010Between 1999 and 2010, an annual census of the White StorkCiconia ciconiabreeding population was carried out in Slovenia using standardised methods. The Stork's population was concentrated in the NE and SE parts of Slovenia. In the 1999-2010 period, the breeding range of its population in Slovenia expanded in NW direction (the Savska ravan region), in SW direction (the Notranjsko podolje and Pivško podolje regions), but the species also colonized a part between Central and SE Slovenia (Dolenjsko podolje). Between 193 and 240 pairs were breeding during the study period, 209 pairs on average (HPa). The largest number of breeding pairs was recorded in 2004, the smallest in 2005. During the study period, breeding pairs (HPa) occupied 350 discrete nests in total. Average number of breeding pairs that raised juveniles (HPm) was 161. The highest fecundity was recorded in 2004, when 534 juveniles (JZG) fledged, the lowest in 2006, with only 219 fledged juveniles. On average, 414 juveniles fledged per year. The breeding pairs' (JZa) average breeding success in these 12 years was 2.02, the highest in 2000 (2.41), the lowest in 2006 (1.09). Average breeding success for the successful breeding pairs (JZm) was 2.57. The highest was in 2007 (2.94), the lowest in 2006 (2.07). The largest number of breeding pairs in 2004 and 2008 can be explained by the favourable fecundity in the population in 2000 and 2004, as juveniles become sexually mature at the age of 3-5 years, and at that age they generally return to the breeding grounds for the first time. The lowest number of breeding pairs and poor breeding success in 2005 and 2006 was caused by late arrival of White Storks to the breeding grounds and by unfavourable weather conditions during the breeding period. The pattern of nests placement did not change generally during the last 12 years. The largest proportion of nests was positioned on various kinds of poles (81%) and on chimneys (18%). In total, 27 area surveyors and 239 assistants helped in census realisation.

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