Sarus Crane abstracts
These abstracts on Sarus Crane research in Australia and India are posted with kind permission of the authors, with links to full content in scientific journals. Please contact the author for permission if wishing to repost a paper abstract elsewhere.
John D A Grant, north Queensland ornithologist
John Grant has surveyed recruitment in the wintering population of Sarus Crane on the Atherton Tablelands, far north Queensland, since 1997
Grant, John DA. ‘Recruitment rate of Sarus Cranes (Grus antigone) in northern Queensland.’ Emu 105, no. 4 (2006): 311-315.
Title Recruitment rate of Sarus Cranes (Grus antigone) in northern Queensland
Abstract Annual recruitment of Sarus Cranes was estimated from 1997 to 2002, by means of observed proportions of juveniles in non-breeding flocks on the Atherton Tableland. Survey conditions were considered free of confounding influences as to provide the first accurate estimate of recruitment for the Australian population of this species. Mean recruitment over the 6-year period was 6.58%, with no significant variation between years. Comparison with other crane populations indicates that the recruitment rate is low, but further detailed data are needed to evaluate properly the status of the population.
K S Gopi Sundar, Director Program Sarusscape
K S Gopi Sundar has intensively studied Sarus Cranes, wetlands and human communities in India since 1998 and is Director of Program SarusScape, a collaboration between the International Crane Foundation and Nature Conservation Foundation (India).
Sundar, KS Gopi. ‘Effectiveness of road transects and wetland visits for surveying Black-necked Storks Ephippiorhynchus asiaticus and Sarus Cranes Grus antigone in India.’ Forktail 21 (2005): 27.
Title Effectiveness of road transects and wetland visits for surveying Black-necked Storks Ephippiorhynchus asiaticus and Sarus Cranes Grus antigone in India
Abstract I surveyed Black-necked Storks Ephippiorhynchus asiaticus and Sarus Cranes Grus antigone in Etawah and Mainpuri districts, Uttar Pradesh, India, by carrying out counts at five wetlands and along a 105-km road transect each month from December 2000 to February 2002. The results were compared to the known population sizes in the area as determined from spot-mapping of territories. On average, road transects detected 17.9% of Black-necked Storks and 35% of territorial Sarus Crane pairs. Densities and encounter rates from road transect data correlated with known numbers of Black-necked Storks. For Black-necked Storks, pairs were more likely to be detected than families, whereas the converse was true for Sarus Cranes. Wetland sites held only 20.5% of Black-necked Storks and 8.9% of territorial Sarus Crane pairs (although wetlands held 65% of non-breeding cranes). Consequently, wetland counts alone were not found to be effective for surveying these two species. On average, they recorded only 1.3% of all Black-necked Stork pairs. Too few Sarus Crane pairs were reliably identifiable in wetlands to determine their sighting probability. Road transects that pass wetland sites and that are carried out in late winter will provide the most accurate data for both species.
Sundar, KS Gopi, and BC Choudhury. ‘Mortality of Sarus Cranes (Grus antigone) due to electricity wires in Uttar Pradesh, India.’ Environmental Conservation 32, no. 3 (2005): 260-269.
Title Mortality of Sarus Cranes (Grus antigone) due to electricity wires in Uttar Pradesh, India
Abstract Although overhead electrical wires are known to have caused severe declines of bird populations, there are no studies in India that address this danger, even for endangered species. Rates of mortality, factors affecting mortality and population effects of electrical wires on the globally endangered sarus crane (Grus antigone) were assessed for breeding and non-breeding cranes in Etawah and Mainpuri districts, Uttar Pradesh, India. Non-breeding cranes were most susceptible to wires and, within territories, mortalities were higher for pre-dispersed young. Similar proportions of non-breeding and breeding cranes were killed, together accounting for nearly 1% of the total sarus crane population annually. Supply wires accounted for the majority of sarus crane deaths, and only non-breeding cranes were killed by both supply and high-tension power lines. Non-breeding crane deaths at roost sites were correlated with numbers of roosting birds and numbers of wires at each site. Over 40% of 251 known sarus crane territories had at least one overhead wire posing a risk to breeding adults and pre-dispersed young. A risk index for wires over territories of cranes was computed; mortality was not affected by increasing the number and therefore risk posed by wires. Most crane deaths in territories occurred as a result of wires at edges of territories. Wires around roosting sites, territoriality and age of sarus cranes appear to be the most important factors affecting their mortality due to wires. Mitigation measures will be most effective around roost sites and for wires that border territories of breeding pairs.
Sundar, KS Gopi. ‘Instances of successful raising of three chicks by Sarus Crane Grus antigone pairs.’ Forktail 22 (2006): 124.
Title Instances of successful raising of three chicks by Sarus Crane Grus antigone pairs
Summary Successful breeding pairs of cranes in the genus Grus characteristically raise one or two chicks each season,since their clutch size is generally one or two eggs. Very few nests have three or four eggs (Walkinshaw 1973, Johnsgard 1983, Littlefield 1995, Allan 1996, Meine and Archibald 1996). Studies on the breeding biology of Sarus Cranes Grus antigone in India have shown that this species rarely has clutch sizes of three (Walkinshaw 1973, K. Kathju in litt. 2006) or four (Sundar and Choudhury 2005), and breeding pairs characteristically raise one or two chicks each year (Sundar and Choudhury 2003). Here I describe two instances of pairs fledging three chicks successfully.
Sundar, KS Gopi. ‘Are rice paddies suboptimal breeding habitat for Sarus Cranes in Uttar Pradesh, India?’ The Condor 111, no. 4 (2009): 611-623.
Title Are rice paddies suboptimal breeding habitat for Sarus Cranes in Uttar Pradesh, India?
Abstract The globally threatened Sarus Crane (Grus antigone) has low annual productivity and occurs mostly in landscapes dominated by agriculture; it is therefore vulnerable to extinction caused by human-related disturbance and mortality. The Sarus Crane's increased use of rice paddies as breeding habitat has fueled concerns that the species is being forced to use suboptimal habitats. To assess the issue, I studied nest-site selection and quantified nest and brood survival of Sarus Cranes in Uttar Pradesh, northern India, during 2000 and 2001 and evaluated differences between natural wetlands and rice paddies. The cranes preferred wetlands as nesting habitat at the levels of both the landscape and individual territory. The success (daily survival rate) of nests closer to roads was lower, suggesting that human-related mortality played a role. The effect of habitat on nest success was equivocal, suggesting that rice fields per se are not suboptimal as nesting sites. This result is unique to this area, suggesting that favorable attitudes of farmers still allow Sarus Cranes to nest in rice paddies. Broods hatching later and those in territories with fewer wetlands had a lower probability of survival. Vegetation changes and disturbance during crop harvesting likely decreased brood survival. Maintaining a patchwork of shallow wetlands in rice-dominated landscapes and ensuring that farmers retain a positive attitude toward the species are crucial for survival of Sarus Crane nests and broods.
Sundar, KS Gopi, and S. Subramanya. ‘Bird use of rice fields in the Indian subcontinent.’ Waterbirds 33, no. sp1 (2010): 44-70.
Title Bird use of Rice Fields in the Indian Subcontinent
Abstract The Indian subcontinent has the world's highest cropland cover per unit area with rice (Oryza sativa) being the second-most important crop, and is home to nearly 1,300 species of birds. The significance of rice fields as bird habitat in the region is not well understood and the subject is reviewed using a combination of published and secondary information. Rice fields in the subcontinent are used by at least 351 species, although only 2.7% of birds occurring in the subcontinent breed in rice fields. The spread of rice cultivation and its attendant secondary habitats may have contributed to the increase in range and population of 64 common species but is threatening hundreds of other species, many of conservation concern. Most work in the region has focused on birds as pests of rice. Few studies have been conducted on the habits of birds that use rice fields and fewer still have compared how rice fields and similar natural habitats differ. Although rice harvesting has caused nest mortality for breeding birds, there is no comparable information from natural habitats. The guild structure of birds in rice fields is similar to that overall in the region except for a higher representation of carnivores. Rice fields are used primarily by grassland and wetland species. There are large information gaps that require filling to be able to ascertain the utility or impact of rice fields to bird populations and, thus, many research opportunities.
Sundar, KS Gopi. ‘Agricultural intensification, rainfall patterns, and large waterbird breeding success in the extensively cultivated landscape of Uttar Pradesh, India.’ Biological Conservation 144, no. 12 (2011): 3055-3063.
Title Agricultural intensification, rainfall patterns, and large waterbird breeding success in the extensively cultivated landscape of Uttar Pradesh, India
Abstract In countries with high human populations, using agricultural areas as multifunctional systems to produce food for humans and retain wildlife may be an efficient conservation strategy for many species. Inclusion of natural habitat and species requirements on agricultural landscapes explicitly into planning processes are precluded by lack of information on drivers of species persistence. Climate change is an additional emerging complexity, and adaptation plans for agricultural landscapes are biased towards intensification to secure long-range food production. I examine the conservation potential of an agricultural landscape in two districts of Uttar Pradesh, north India where agricultural intensification and altered rainfall patterns are predicted to occur. I assess stressors affecting breeding success over eight years of two large waterbirds of conservation concern – Sarus Cranes and Black-necked Storks. Both species had high breeding success that improved with total rainfall and more wetlands in breeding territories. Agricultural and township expansions deteriorated territory quality and reduced breeding success. Sarus Crane populations were predicted to decline relatively rapidly if development activities continued to displace breeding pairs. Black-necked Storks appeared resilient over the long-term notwithstanding reduced breeding success in low-rainfall years. Waterbird nesting habitats (wetlands and trees) were retained in Uttar Pradesh as community lands by villages and by state government via legal provisions suggesting the utility of multiple conservation approaches. Incorporating species requirements explicitly, alongside traditional land use practices conducive for habitat conservation, into adaptation planning and conservation policy will be necessary to retain long-term multifunctionality of such agricultural landscapes.
Sundar, KS Gopi, and Swati A. Kittur. ‘Methodological, temporal and spatial factors affecting modeled occupancy of resident birds in the perennially cultivated landscape of Uttar Pradesh, India.’ Landscape Ecology 27, no. 1 (2012): 59-71.
Title Methodological, temporal and spatial factors affecting modeled occupancy of resident birds in the perennially cultivated landscape of Uttar Pradesh, India
Abstract Biodiversity persistence in non-woody tropical farmlands is poorly explored, and multi-species assessments with robust landscape-scale designs are sparse. Modeled species occupancy in agricultural mosaics is affected by multiple factors including survey methods (convenience-based versus systematic), landscape-scale agriculture-related variables, and extent of remnant habitat. Changes in seasonal crops can additionally alter landscape and habitat conditions thereby influencing species occupancy. We investigated how these factors affect modeled occupancy of 56 resident bird species using a landscape-scale multi-season occupancy framework across 24 intensively cultivated and human-dominated districts in Uttar Pradesh state, north India. Convenience-based roadside observations provided considerable differences in occupancy estimates and associations with remnant habitat and intensity of cultivation relative to systematic transect counts, and appeared to bias results to roadside conditions. Modeled occupancy of only open-area species improved with increasing intensity of cultivation, while remnant habitat improved modeled occupancy of scrubland, wetland and woodland species. Strong seasonal differences in occupancy were apparent for most species across all habitat guilds. Further habitat loss will be most detrimental to resident scrubland, wetland and woodland species. Uttar Pradesh's agricultural landscape has a high conservation value, but will require a landscape-level approach to maintain the observed high species richness. Obtaining ecological information from unexplored landscapes using robust landscape-scale surveys offers substantial advantages to understand factors affecting species occupancy, and is necessary for efficient conservation planning.