Effects of breeding success, age and sex on breeding dispersal of a reintroduced population of the Crested Ibis (Nipponia nippon) in Ningshan County, China

SummaryReintroduction projects usually attempt to re-establish a self-sustaining population of endangered species within their historical ranges through the release of captive-bred individuals into the wild. We studied the breeding biology and nesting success of a reintroduced population of Crested Ibis Nipponia nippon in Ningshan County on the south slope of the Qinling Mountains of Shaannxi Province, China. From May 2007 to October 2011, 56 captive-bred individuals, composed of 26 females and 30 males, were released into the area and monitored using radio-telemetry. The average age of individuals at release was 5.2 ± 2.5 years for females and 6.4 ± 2.9 years for males. Mean clutch size was 3.14±1.06 (range 1-5). Mean number of fledglings per active nest was 1.57 ± 1.03 and mean number of fledglings per successful nest was 2.00 ± 0.87. Most of the fledglings survived to complete their post-fledging dispersal. Mean annual survival rate was 0.552 ± 0.064 for all released birds, 0.815 ± 0.054 for breeders, and 0.515 ± 0.058 for first year fledglings. The average number of young produced/year/pair was 1.57 ± 1.03 and the growth rate (λ) of the reintroduced population was 1.2193. We confirmed that starvation and predation by King Rat Snake Elaphe carinata were the main causes of death of released individuals, nestlings and fledglings. This is the first attempt to reintroduce captive-bred Crested Ibis to former natural habitat. The ability of captive-bred ibis to survive and breed successfully bodes well for future releases of this and other endangered species.

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Survival rates of a reintroduced population of the Crested Ibis Nipponia nippon in Ningshan County (Shaanxi, China)

Bird Conservation International ◽

10.1017/s0959270916000666 ◽

2017 ◽

Vol 28 (1) ◽

pp. 145-156 ◽

Cited By ~ 4

Author(s):

YANFANG LI ◽

XINPING YE ◽

MIN WANG ◽

XIA LI ◽

RONG DONG ◽

...

Keyword(s):

Survival Rate ◽

Survival Rates ◽

Shaanxi Province ◽

Factors Affecting ◽

Annual Survival ◽

Nipponia Nippon ◽

Crested Ibis ◽

Adult Sex Ratio ◽

Capture Recapture ◽

Reintroduced Population

SummaryA reintroduction project for the endangered Crested Ibis Nipponia nippon was conducted in Ningshan County (Shaanxi Province) on May 31, 2007. Post-release monitoring of the survival of the reintroduced population was carried out extensively from 2008 to 2015. Data collected over eight years after release were used to estimate the annual survival rate for different cohorts using a Cormack-Jolly-Seber model with capture-recapture data. The mean annual survival rates for all individuals were estimated to be 0.738 (95% CI: 0.547–0.801) and 0.752 (95% CI: 0.478–0.887) for released birds. For different age classes in the recipient population, the survival rates were estimated to be 0.384 (95% CI: 0.277–0.504), 0.853 (95% CI: 0.406–0.978), and 0.812 (95% CI: 0.389–0.950) for yearlings, juveniles and adults, respectively. The higher mortality for yearlings has greatly decreased the survival rate and our focal population was indeed sensitive to changes in yearling survival. Therefore, effective protection of yearlings was crucial to population persistence, as well as to juveniles and adults. The large proportion of mature individuals in our focal population indicated a gradually growing population. There was a slight bias towards males in the adult sex ratio with the increase of wild-born offspring, but it was not statistically significant. Therefore, we conclude that the primary goal of establishing a self-sustaining population of the Crested Ibis in part of their historical range has been achieved. Finally, we discuss factors affecting the survival of the reintroduced population and we propose some changes for future management of endangered species.

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Reproductive success of the Crested Ibis Nipponia nippon

Bird Conservation International ◽

10.1017/s0959270906000499 ◽

2006 ◽

Vol 16 (4) ◽

pp. 325-343 ◽

Cited By ~ 14

Author(s):

XIAOPING YU ◽

NAIFA LIU ◽

YONGMEI XI ◽

BAOZHONG LU

Keyword(s):

Breeding Success ◽

Large Degree ◽

Limited Range ◽

Central China ◽

Shaanxi Province ◽

Limiting Factor ◽

Protection Measures ◽

Nipponia Nippon ◽

Crested Ibis ◽

In The Wild

The last remaining population of the Crested Ibis Nipponia nippon in the wild was studied in the Qinling Mountains, Yangxian County, Shaanxi Province, central China, over 24 breeding seasons with particular attention being paid to the nesting behaviour and breeding success. The average clutch size varied significantly among years (2.84 ± 0.77; n = 271), suggesting that food abundance, which was distinct in different areas, was indeed a limiting factor. The mean hatching success was 80.2%, and ranged from 35.7% to 100%. Egg losses were due to three reasons: infertility or the eggs being addled, predation, and human disturbance. Three reasons accounting for chick death were highlighted: shortage of food, predation, and disturbance from local inhabitants. However, the overall breeding success of the Crested Ibis, which averaged 65.6%, was much higher than that of many nidicolous birds and was clearly dependent not only on the stability of pair maintenance but also on human conservation and protection measures. The relatively higher proportion of unsuccessful nests at altitudes between 500–700 m and 701–900 m was linked with the more frequent human activities, predation and lower stability of nest-trees in such areas. The fact that there was no significant variation in the number of successful nests or breeding success across different altitudinal zones demonstrated that, to a large degree, habitats used by the Crested Ibis were now suitable for breeding. The rapid increase in the species' numbers in recent years has been achieved through effective protection measures, including legislation, management of population and habitat, and regular surveys and monitoring. A reintroduction programme has been put into effect, protecting the population from a chance catastrophe such as communicable diseases within its limited range.

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Post-fledging dispersal and habitat use of a reintroduced population of the Crested Ibis (Nipponia nippon)

Avian Research ◽

10.1186/s40657-014-0007-5 ◽

2014 ◽

Vol 5 (1) ◽

Cited By ~ 5

Author(s):

Zhiping Huo ◽

Junfeng Guo ◽

Xia Li ◽

Xiaoping Yu

Keyword(s):

Habitat Use ◽

Nipponia Nippon ◽

Crested Ibis ◽

Reintroduced Population

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Experimental reintroduction revealed novel reproductive variation in Crested Ibis Nipponia nippon

10.7287/peerj.preprints.817 ◽

2015 ◽

Author(s):

Dongping Liu ◽

Chao Wang ◽

Baoping Qing ◽

Jun Lu

Keyword(s):

Phenotypic Plasticity ◽

Central China ◽

Dispersal Capacity ◽

Nipponia Nippon ◽

Colonial Nesting ◽

Monogamous Species ◽

Crested Ibis ◽

Biased Sex Ratio ◽

Adaptive Phenotypic Plasticity ◽

Reintroduced Population

The Crested Ibis Nipponia Nippon formerly occurred throughout East Asia, but since 1981 its unique population has been confined to a narrow area in Central China. During 2004-2005, 23 Crested Ibises were experimentally reintroduced to an isolated basin in Qinling Mountains, where they and their offspring exhibited variation in reproduction never observed in wild population. Crested Ibis has been considered to be a monogamous species, and breeding pair is solitary and territorial in breeding season. However, 3.4% of breeding females exhibited polyandry and 43.1% of nests were observed in colony in the reintroduced population during 2006-2014. The mating system flexibility is likely related to male-biased sex ratio in the small isolated reintroduced population, due to greater dispersal capacity by female. The colonial nesting is attributed to the availability of large nest trees and abundant food supply. First nest failure in reintroduced population occurred much earlier than that in wild, which resulted in significantly higher probability of renesting. The phenotypic plasticity in Crested Ibis may play important role in the restoration of this critical endangered species under a changing environment, and future reintroductions provide opportunity to further understand the degree and cost of adaptive phenotypic plasticity in Crested Ibis.

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Survival rates and reproductive ecology of a reintroduced population of the Asian Crested Ibis Nipponia nippon in Shaanxi Qianhu National Wetland Park, China

Bird Conservation International ◽

10.1017/s0959270920000593 ◽

2020 ◽

pp. 1-10

Author(s):

MIN LI ◽

XINPING YE ◽

RONG DONG ◽

XUEJING ZHANG ◽

HU ZHANG ◽

...

Keyword(s):

Survival Rates ◽

Bird Species ◽

Factors Affecting ◽

Nipponia Nippon ◽

Crested Ibis ◽

Viable Population ◽

Capture Recapture ◽

Reintroduced Population ◽

Living Organisms ◽

S Model

Summary Reintroductions aim to re-establish a viable population within the indigenous range of living organisms, especially of threatened species. The population of the Asian Crested Ibis Nipponia nippon, a well-known ‘Endangered’ bird species, has increased over 100 times since wild populations were rediscovered in 1981, and several reintroduction projects were subsequently carried out in its former range. An experimental release of the Asian Crested Ibis was conducted in Qianhu National Wetland Park located in the southern part of the Loess Plateau, China. It is vitally important to monitor released birds (at least their survival and breeding), to inform subsequent releases in other suitable sites. During extensive post-release monitoring, data on capture-recapture and reproductive status were obtained using banding, radiotelemetry, and field observations. Using the Cormack-Jolly-Seber (C-J-S) model, the average annual survival rates were estimated to be 0.569 (95% CI: 0.353–0.762) for released individuals and 0.643 (95% CI: 0.038–0.987) for all individuals. From 2014 to 2018, a total of 14 breeding pairs produced 28 eggs and 10 fledglings with successful reproduction of the second generation. The mean clutch size was 2.07 ± 0.25 (n = 29), and the breeding success was 34.5%. Predation and poor habitat quality have been shown to be the main factors affecting the reintroduced population at establishment stage. Some management suggestions at the metapopulation and ecosystem levels, including further release, predator control and habitat improvement, have been proposed.

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Experimental reintroduction revealed novel reproductive variation in Crested Ibis Nipponia nippon

10.7287/peerj.preprints.817v1 ◽

2015 ◽

Author(s):

Dongping Liu ◽

Chao Wang ◽

Baoping Qing ◽

Jun Lu

Keyword(s):

Phenotypic Plasticity ◽

Central China ◽

Dispersal Capacity ◽

Nipponia Nippon ◽

Colonial Nesting ◽

Monogamous Species ◽

Crested Ibis ◽

Biased Sex Ratio ◽

Adaptive Phenotypic Plasticity ◽

Reintroduced Population

The Crested Ibis Nipponia Nippon formerly occurred throughout East Asia, but since 1981 its unique population has been confined to a narrow area in Central China. During 2004-2005, 23 Crested Ibises were experimentally reintroduced to an isolated basin in Qinling Mountains, where they and their offspring exhibited variation in reproduction never observed in wild population. Crested Ibis has been considered to be a monogamous species, and breeding pair is solitary and territorial in breeding season. However, 3.4% of breeding females exhibited polyandry and 43.1% of nests were observed in colony in the reintroduced population during 2006-2014. The mating system flexibility is likely related to male-biased sex ratio in the small isolated reintroduced population, due to greater dispersal capacity by female. The colonial nesting is attributed to the availability of large nest trees and abundant food supply. First nest failure in reintroduced population occurred much earlier than that in wild, which resulted in significantly higher probability of renesting. The phenotypic plasticity in Crested Ibis may play important role in the restoration of this critical endangered species under a changing environment, and future reintroductions provide opportunity to further understand the degree and cost of adaptive phenotypic plasticity in Crested Ibis.

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