Annual Survival Rate Estimate of Satellite Transmitter–Marked Eastern Population Greater Sandhill Cranes

2015 ◽  
Vol 6 (2) ◽  
pp. 464-471 ◽  
Author(s):  
David L. Fronczak ◽  
David E. Andersen ◽  
Everett E. Hanna ◽  
Thomas R. Cooper
Keyword(s):  
Survival Rate ◽  
Population Size ◽  
Management Strategies ◽  
Early Summer ◽  
Rate Estimate ◽  
Satellite Transmitter ◽  
Eastern Population ◽  
Annual Survival ◽  
Sandhill Crane ◽  
Sandhill Cranes

Abstract Several surveys have documented the increasing population size and geographic distribution of Eastern Population greater sandhill cranes Grus canadensis tabida since the 1960s. Sport hunting of this population of sandhill cranes started in 2012 following the provisions of the Eastern Population Sandhill Crane Management Plan. However, there are currently no published estimates of Eastern Population sandhill crane survival rate that can be used to inform harvest management. As part of two studies of Eastern Population sandhill crane migration, we deployed solar-powered global positioning system platform transmitting terminals on Eastern Population sandhill cranes (n  =  42) at key concentration areas from 2009 to 2012. We estimated an annual survival rate for Eastern Population sandhill cranes from data resulting from monitoring these cranes by using the known-fates model in the MARK program. Estimated annual survival rate for adult Eastern Population sandhill cranes was 0.950 (95% confidence interval  =  0.885–0.979) during December 2009–August 2014. All fatalities (n  =  5) occurred after spring migration in late spring and early summer. We were unable to determine cause of death for crane fatalities in our study. Our survival rate estimate will be useful when combined with other population parameters such as the population index derived from the U.S. Fish and Wildlife Service fall survey, harvest, and recruitment rates to assess the effects of harvest on population size and trend and evaluate the effectiveness of management strategies.

scholarly journals Demographic rates of northern royal albatross at Taiaroa Head, New Zealand

2014 ◽  
Author(s):  
Yvan Richard ◽  
Lyndon Perriman ◽  
Chris Lalas ◽  
Edward R. Abraham
Keyword(s):  
New Zealand ◽  
Survival Rate ◽  
Population Size ◽  
Total Population ◽  
Adult Survival ◽  
Total Population Size ◽  
Annual Survival ◽  
Demographic Rates ◽  
Age At First Breeding ◽  
The Mean

Demographic rates, such as annual survival rate, are generally difficult to estimate for long-lived seabirds, because of the length of time required for this kind of study and the remoteness of colonies. However, a small colony of northern royal albatross (Diomedea sanfordi) established itself on the mainland of New Zealand at Taiaroa Head, making possible regular banding and monitoring of its individuals since the first chick fledged, in 1938. Data on the presence/absence of birds, as well as on breeding outcomes, were available for the period from 1989–90 to 2011–12, and included 2128 annual resightings of 355 banded individuals of known age. The main goal of the present study was to estimate the annual survival rate of juveniles, pre-breeders, and adults at Taiaroa Head. These rates were estimated simultaneously in a single Bayesian multi-state capture-recapture model. Several models were fitted to the data, with different levels of complexity. From the most parsimonious model, the overall annual adult survival rate was estimated as 0.950 (95% c.i.: 0.941–0.959). In this model, adult survival declined with age, from 0.976 (95% c.i.: 0.963–0.988) at 6 years, the minimum age at first breeding, to 0.915 (95% c.i.: 0.879–0.946) at 40 years. Mean annual survival of pre-breeders was 0.966 (95% c.i.: 0.950–0.980), and 0.933 (95% c.i.: 0.908–0.966) for juveniles. There was no discernible difference in survival between males and females, and there was no apparent trend in survival over time. Estimates of other demographic rates were also obtained during the estimation process. The mean age at first return of juveniles to the colony was estimated as 4.8 years (95% c.i.: 4.6–5.1), and the mean age at first breeding as 8.9 years (95% c.i.: 8.5–9.3). Because all the birds of the colony were banded, it was possible to estimate the total population size. The number of northern royal albatross present annually at the Taiaroa Head colony has doubled since 1989–90, and the current total population size was estimated to be over 200 individuals. The ratio of the total population size to the number of annual breeding pairs varied from 5 to 12 among years, with an overall mean of 7.65 (95% c.i.: 7.56–7.78), and this high variability highlights the need for a sufficient number of surveys of seabird breeding populations before reliable conclusions on population trends can be made. Although long-term data allowed estimates of demographic rates of northern royal albatross at Taiaroa Head, the location of the colony and the ongoing management by staff mean that the population dynamics may differ from those of the main population on the Chatham Islands.

scholarly journals Artificial incubation, egg replacement and adoptive parents in bird management: a test with Lesser Elaenia Elaenia chiriquensis

2012 ◽  
Vol 23 (3) ◽  
pp. 283-295 ◽  
Author(s):  
YONARA LOBO ◽  
MIGUEL ÂNGELO MARINI
Keyword(s):  
Survival Rate ◽  
Population Size ◽  
Nest Success ◽  
Management Strategies ◽  
Adoptive Parents ◽  
Hatching Rate ◽  
Daily Survival Rate ◽  
Breeding Parameters ◽  
Daily Survival ◽  
Artificial Incubation

SummaryReducing the time that birds’ eggs are exposed during incubation in the wild is a management strategy with the potential to reduce nest predation rates, enhance breeding success and increase the population size of endangered species. We tested whether manipulation of clutches through artificial incubation of Lesser Elaenia Elaenia chiriquensis eggs and subsequent reintroduction of new-born nestlings to their original nest, and the use of adoptive parents, were efficient ways of increasing the population size of this species. We evaluated the financial cost and benefit of three different management strategies of artificial egg incubation with reintroduction of nestlings to the original nest. We searched for nests and manipulated eggs during the breeding seasons of 2009 and 2010 in a savanna reserve in central Brazil. Real eggs were replaced by artificial eggs and artificially incubated. The following breeding parameters were monitored: hatching rate, fledgling productivity, daily survival rate of nestlings and nest success. The effect of nest monitoring frequency (daily or every 3–4 days) on breeding parameters was also tested. Hatching rate was much higher amongst artificially incubated eggs than naturally incubated eggs. Artificially incubated clutches presented higher rates of fledgling production and apparent nest success than non-manipulated clutches. Clutch manipulation did not interfere with nestling daily survival rate. Daily monitoring did not have negative effects. The clutch manipulation methodology we used proved to be viable and is a potential tool for increasing population size.

scholarly journals Demographic rates of northern royal albatross at Taiaroa Head, New Zealand

2014 ◽  
Author(s):  
Yvan Richard ◽  
Lyndon Perriman ◽  
Chris Lalas ◽  
Edward R. Abraham
Keyword(s):  
New Zealand ◽  
Survival Rate ◽  
Population Size ◽  
Total Population ◽  
Adult Survival ◽  
Total Population Size ◽  
Annual Survival ◽  
Demographic Rates ◽  
Age At First Breeding ◽  
The Mean

Demographic rates, such as annual survival rate, are generally difficult to estimate for long-lived seabirds, because of the length of time required for this kind of study and the remoteness of colonies. However, a small colony of northern royal albatross (Diomedea sanfordi) established itself on the mainland of New Zealand at Taiaroa Head, making possible regular banding and monitoring of its individuals since the first chick fledged, in 1938. Data on the presence/absence of birds, as well as on breeding outcomes, were available for the period from 1989–90 to 2011–12, and included 2128 annual resightings of 355 banded individuals of known age. The main goal of the present study was to estimate the annual survival rate of juveniles, pre-breeders, and adults at Taiaroa Head. These rates were estimated simultaneously in a single Bayesian multi-state capture-recapture model. Several models were fitted to the data, with different levels of complexity. From the most parsimonious model, the overall annual adult survival rate was estimated as 0.950 (95% c.i.: 0.941–0.959). In this model, adult survival declined with age, from 0.976 (95% c.i.: 0.963–0.988) at 6 years, the minimum age at first breeding, to 0.915 (95% c.i.: 0.879–0.946) at 40 years. Mean annual survival of pre-breeders was 0.966 (95% c.i.: 0.950–0.980), and 0.933 (95% c.i.: 0.908–0.966) for juveniles. There was no discernible difference in survival between males and females, and there was no apparent trend in survival over time. Estimates of other demographic rates were also obtained during the estimation process. The mean age at first return of juveniles to the colony was estimated as 4.8 years (95% c.i.: 4.6–5.1), and the mean age at first breeding as 8.9 years (95% c.i.: 8.5–9.3). Because all the birds of the colony were banded, it was possible to estimate the total population size. The number of northern royal albatross present annually at the Taiaroa Head colony has doubled since 1989–90, and the current total population size was estimated to be over 200 individuals. The ratio of the total population size to the number of annual breeding pairs varied from 5 to 12 among years, with an overall mean of 7.65 (95% c.i.: 7.56–7.78), and this high variability highlights the need for a sufficient number of surveys of seabird breeding populations before reliable conclusions on population trends can be made. Although long-term data allowed estimates of demographic rates of northern royal albatross at Taiaroa Head, the location of the colony and the ongoing management by staff mean that the population dynamics may differ from those of the main population on the Chatham Islands.

scholarly journals A Three-Pronged Approach to Studying Sublethal Insecticide Doses: Characterising Mosquito Fitness, Mosquito Biting Behaviour, and Human/Environmental Health Risks

Insects ◽  
2021 ◽  
Vol 12 (6) ◽  
pp. 546
Author(s):  
Mara Moreno-Gómez ◽  
Rubén Bueno-Marí ◽  
Miguel. A. Miranda
Keyword(s):  
Environmental Health ◽  
Population Size ◽  
Mosquito Species ◽  
Management Strategies ◽  
Adult Mortality ◽  
Negative Control ◽  
Environmental Health Risks ◽  
Vector Management ◽  
Sublethal Doses ◽  
Biting Behaviour

Worldwide, pyrethroids are one of the most widely used insecticide classes. In addition to serving as personal protection products, they are also a key line of defence in integrated vector management programmes. Many studies have assessed the effects of sublethal pyrethroid doses on mosquito fitness and behaviour. However, much remains unknown about the biological, physiological, demographic, and behavioural effects on individual mosquitoes or mosquito populations when exposure occurs via spatial treatments. Here, females and males of two laboratory-reared mosquito species, Culex pipiens and Aedes albopictus, were exposed to five different treatments: three doses of the pyrethroid prallethrin, as well as an untreated and a negative control. The effects of each treatment on mosquito species, sex, adult mortality, fertility, F1 population size, and biting behaviour were also evaluated. To compare knockdown and mortality among treatments, Mantel–Cox log-rank tests were used. The results showed that sublethal doses reduced mosquito survival, influencing population size in the next generation. They also provided 100% protection to human hosts and presented relatively low risks to human and environmental health. These findings emphasise the need for additional studies that assess the benefits of using sublethal doses as part of mosquito management strategies.

Effect of Orthene® on an unconfined population of the meadow vole (Microtus pennsylvanicus)

1986 ◽  
Vol 64 (1) ◽  
pp. 243-250 ◽  
Author(s):  
David A. Jett ◽  
James D. Nichols ◽  
James E. Hines
Keyword(s):  
Survival Rate ◽  
Population Size ◽  
Weight Change ◽  
Relative Weight ◽  
Reproductive Activity ◽  
Microtus Pennsylvanicus ◽  
Field Application ◽  
Meadow Vole ◽  
Old Field ◽  
Insecticide Treatment

The possible impact on Microtus pennsylvanicus of ground applications of Orthene® insecticide was investigated in old-field habitats in northern Maryland during 1982 and 1983. The treatment grids in 1982 and 1983 were sprayed at 0.62 and 0.82 kg active ingredient/ha, respectively. A capture–recapture design robust to unequal capture probabilities was utilized to estimate population size, survival, and recruitment. Data on reproductive activity and relative weight change were also collected to investigate the effect of the insecticide treatment. There were no significant differences in population size or recruitment between control and treatment grids which could be directly related to the treatment. Survival rate was significantly lower on the treatment grid than on the control grid after spraying in 1983; however, survival rate was higher on the treatment grid after spraying in 1982. Significantly fewer pregnant adults were found on the treatment grid after spraying in 1982, whereas the proportions of voles lactating or with perforate vaginas or open pubic symphyses were slightly higher or remained unchanged during this period. Relative weight change was not affected by the treatment. Results do not indicate any pattern of inhibitory effects from the insecticide treatment. Field application of Orthene® did not have an adverse effect on this Microtus population.

Host–Parasite Behavioral Interactions in a Recently Introduced, Whooping Crane Population

2015 ◽  
Vol 6 (1) ◽  
pp. 220-226 ◽  
Author(s):  
Richard S. King ◽  
Patrick C. McKann ◽  
Brian R. Gray ◽  
Michael S. Putnam
Keyword(s):  
Reproductive Performance ◽  
Black Flies ◽  
Behavioral Differences ◽  
Whooping Crane ◽  
Black Fly ◽  
Grus Canadensis ◽  
Sandhill Crane ◽  
Conservation History ◽  
Whooping Cranes ◽  
Sandhill Cranes

Abstract The whooping crane Grus americana has a long conservation history, but despite multiple attempts across North America, introduction success is lacking. Recently introduced, captively reared whooping cranes have had periods of poor reproductive performance in central Wisconsin that sometimes coincided with black fly (Diptera: Simuliidae) emergences. Sandhill crane Grus canadensis reproductive performance in central Wisconsin is approximately double that of whooping cranes. We used comfort behaviors as a measure of black fly harassment to infer whether behavioral differences existed between nesting sandhill cranes and nesting whooping cranes and between successful and unsuccessful whooping crane pairs. To further explore the interaction between black flies and incubating whooping cranes, we examined differences in behaviors between incubating birds and their off-nest mates. Compared to their off-nest mates, incubating whooping cranes exhibited elevated comfort behaviors, suggesting a bird at a nest may experience greater harassment from black flies. Sandhill cranes had elevated head-flicks over whooping cranes. Whooping cranes exhibited more head-rubs than sandhill cranes, and successful whooping crane pairs had elevated head-rubs over pairs that deserted their nests. Behavioral differences between sandhill cranes and whooping cranes as well as differences in reproductive performance, could be explained by exposure to local breeding conditions. Whereas sandhill cranes have nested in the area for hundreds, if not thousands, of years, whooping cranes were only recently introduced to the area. Behavioral differences between the species as well as those between successful and unsuccessful whooping crane pairs could also be explained by the effect of captive exposure, which could affect all whooping crane introductions.

scholarly journals A Study of Population Size and Activity Patterns and Their Relationship to the Prey Species of the Eurasian Lynx Using a Camera Trapping Approach

Animals ◽  
2019 ◽  
Vol 9 (11) ◽  
pp. 864
Author(s):  
Xiaoming Tang ◽  
Shupei Tang ◽  
Xiaoyu Li ◽  
Dalai Menghe ◽  
Wuliji Bao ◽  
...  
Keyword(s):  
Community Structure ◽  
Population Size ◽  
Habitat Management ◽  
Activity Patterns ◽  
Management Strategies ◽  
Camera Trapping ◽  
Ecosystem Functions ◽  
Lynx Lynx ◽  
Eurasian Lynx ◽  
Different Seasons

Revealing the behavioral relationships between predators and their prey is fundamental in understanding the community structure and ecosystem functions of such animals. This study aimed at detecting the population size and activity patterns of Eurasian lynx (Lynx lynx) (along with its prey) by camera trapping monitoring from 2014 to 2017 at the Saihanwula nature reserve in central Inner Mongolia. The total effective trapping days were 29,892 and 20 lynx were identified from 343 trapping photos based on the inner side patterns of their forelimbs. The daily activity rhythms of the lynx overlapped with those of different prey in different seasons. The yearly activity pattern of the lynx was influenced by its main prey’s biology. In conclusion, this study reveals that the activity patterns of the top predator matched those of its prey in different time periods. Habitat management strategies promoting the restoration of prey communities would benefit the lynx in maintaining a stable community structure.

scholarly journals Sandhill Crane, Grus canadensis, Nesting in the Yorkton Wetland Complex, Saskatchewan

2003 ◽  
Vol 117 (2) ◽  
pp. 224
Author(s):  
Ann M. Burke
Keyword(s):  
Open Water ◽  
Adult Mortality ◽  
Grus Canadensis ◽  
Scirpus Acutus ◽  
Sandhill Crane ◽  
Mate Change ◽  
Wetland Complex ◽  
Total Productivity ◽  
Sandhill Cranes ◽  
Hunting Mortality

Surveys for Sandhill Cranes (Grus canadensis) were conducted near Yorkton, Saskatchewan during the summers of 1995, 1996 and 1997. Seven nesting territories were identified and habitat measurements were taken at six nests. All nests were located in the emergent deep marsh zone of open water marshes within residual stands of Hardstem Bulrush (Scirpus acutus). Seven eggs were measured in four nests. Estimated hatching dates ranged from 20 May to 9 June. Total productivity for the three years was 0.80 chick per breeding pair (12 offspring fledged by 15 pairs). Individual pair productivity was impacted by disturbance, mate change, adult mortality, and predation. Hunting mortality may also impact the population.

The Use of Catch-Effort and Tagging Data in Estimating a Flatfish Population

1953 ◽  
Vol 10 (8) ◽  
pp. 459-485 ◽  
Author(s):  
K. S. Ketchen
Keyword(s):  
British Columbia ◽  
Survival Rate ◽  
Total Population ◽  
Average Rate ◽  
Type Estimate ◽  
Annual Survival ◽  
Average Population ◽  
High Production ◽  
The One ◽  
Parophrys Vetulus

By a modification of the DeLury method an estimate is made of the stock of lemon sole (Parophrys vetulus) on the fishing grounds in Hecate Strait, British Columbia. The method is based on (1) the trend in catch of tagged fish per unit of effort in relation to accumulated catch of tagged fish, and (2) the trend in catch of untagged fish per unit of effort in relation to accumulated catch of untagged fish. At the start of the experiment 4.72 million pounds are estimated to have been present, while during the experiment 3.74 million pounds entered the area of fishing, 3.26 million pounds emigrated from it, and 2.54 million pounds were caught.A Petersen-type estimate based on the ratio of tagged to untagged fish was 4.70 million pounds present at the start of the experiment—practically identical with the one derived from catch-effort information. Total population for the year (1950) is estimated as 9.8–12.2 million pounds, including catch and possible emigration prior to the experiment, the stock on the fishing grounds at the start of the experiment, and the immigration subsequently.The average annual survival rate of age VII – age IX lemon soles in Hecate Strait has decreased from 0.770 to 0.614 during the period of growth of the fishery, 1944–1951. From this difference the average rate of exploitation is estimated as 16 to 20 per cent and the average population as 8.9 to 11.5 million pounds. Since this range is nearly the same as the range described above, it is concluded that almost the whole of the Hecate Strait stock was accessible to fishing in 1950, which was a year of unusually high production.

Changes in the number and distribution of Greater Sandhill Cranes in the Eastern Population

2015 ◽  
Vol 86 (4) ◽  
pp. 317-325 ◽  
Author(s):  
Anne E. Lacy ◽  
Jeb A. Barzen ◽  
Dorn M. Moore ◽  
Kristin E. Norris
Keyword(s):  
Eastern Population ◽  
Sandhill Cranes
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