Shorebird Conservation Research Articles

Co‐production in action: Navigating the research‐to‐implementation space in wildlife conservation through a Community of Practice

AbstractEffective conservation practices require addressing the divide between research and implementation. Co‐production, which emphasizes collaboration and diverse knowledge exchange, is increasingly recognized as valuable in conservation to address this challenge, yet empirical insights remain limited. This case study explores using a Community of Practice (CoP) as an avenue for facilitating co‐production in shorebird conservation. Centering researchers and practitioners within implementation initiatives, we evaluate factors enabling a successful CoP and barriers hindering members' experiences. Capacity emerged as the predominant barrier, while the leading factors contributing to CoP success were having a dedicated space to support labor division, relationship building, and informal learning among CoP members. Leveraging our evaluation insights, we offer practical recommendations for structuring a CoP to optimize these benefits and advance the integration of CoPs and co‐production principles in conservation practice.

Spatiotemporal Distribution and Habitat Characteristics of Shorebirds in the Coastal Wetlands of Dalian, Liaoning, China

The coast of Dalian in Liaoning Province, China, is one of the most important habitats for migratory shorebirds along the East Asia–Australasian Flyway. However, the coastal areas of Dalian have been modified extensively by various projects, including reclamation and the construction of aquaculture and port facilities, embankment buildings, cross-sea passages, and wind farms, which have led to significant damage to the coastal habitats of shorebirds. Assessing the spatiotemporal distribution and habitat characteristics of shorebirds is of great importance to biodiversity conservation. The present study involved a 15-month-long survey of shorebirds in nine coastal wetlands of Dalian from August 2021 to October 2022. In total, 31 species of shorebirds, belonging to five families, were recorded. Migratory shorebirds were the most frequently observed, accounting for 77% of the recorded shorebirds. Dunlin (Calidris alpina), Kentish plover (Charadrius alexandrinus), Eurasian curlew (Numenius arquata), and Far Eastern curlew (Numenius madagascariensis) were the most abundant species. Both species richness and species abundance peaked in May and again in September. The Zhuanghe Estuary boasted the highest species diversity, while the Huli Estuary wetland exhibited the greatest species abundance. The type of habitat and the spatial extent of natural wetlands were the main variables influencing the spatial distribution of waterbirds. By identifying the population characteristics and habitat status of shorebirds in Dalian, the results provide support for shorebird conservation and habitat management.

Shorebirds: Threats and Strategies for Conservation

Shorebirds or waders inhabit in the coastal littoral zone and play critical role in the marine ecosystems and environmental monitoring. Ecological services provided by shorebirds include facilitating energy and nutrient transfer; enrich soils to increase biodiversity along with primary and secondary production. Shorebirds are used as indicators of pollution, environmental change, food chain, and climate change. These birds are vulnerable to hunting pressure, habitat changes, disturbance and other threats. Disturbance to roosting or feeding shorebirds is a major concern along coastlines. Shorebirds can adapt to regular disturbances at predictable distances; but some loud, unpredictable disturbances such as shouting, people running, jet skis, helicopters, kite boards, fast and noisy boats, and dogs are the most threatening to them. Anthropogenic stressors such as chemical pollution, fishing, habitat loss, invasive alien species/introduced species, marine debris, oil spills, poaching, and shipping pose threats to the shorebirds. Human activities can affect the shorebirds, either directly or by producing behavioural or physiological impacts. Present review attempts to provide an illustrative and updated account of shorebirds relevant to current status; natural, anthropogenic, and emerging and under-studied threats; and strategies to be adopted for better conservation and restoration of shorebirds. This study suggests that about threats to shorebirds, future research priorities should be given to assess the cumulative effects of anthropogenic stressors on shorebirds and to recommend effective preventive measures.

The Amazon Basin’s rivers and lakes support Nearctic-breeding shorebirds during southward migration

ABSTRACT Identifying the migration routes and stopover sites used by declining species is critical for developing targeted conservation actions. Long-distance migratory shorebirds are among the groups of birds declining most rapidly, yet we frequently lack detailed knowledge about the routes and stopover sites they use during their hemisphere-spanning migrations. This is especially true for species that migrate through mid-continental regions in the Western Hemisphere. We therefore used satellite transmitters to track 212 individuals of 6 shorebird species during their southward migrations—Pluvialis dominica (American Golden-Plover), Limosa haemastica (Hudsonian Godwit), Tringa flavipes (Lesser Yellowlegs), Calidris subruficollis (Buff-breasted Sandpiper), C. melanotos (Pectoral Sandpiper), and Bartramia longicauda (Upland Sandpiper)—as they crossed the Amazon Basin of South America, a region from which reports of shorebird numbers are increasing but remain relatively rare. Our results make clear that the Amazon Basin provides stopover habitat for a large number of shorebirds: more than 74% of individuals tracked crossing the Amazon Basin stopped over in the region for an average of 2–14 days, with some spending the entire nonbreeding season there. All species selected stopover sites along the region’s many rivers and lakes, while within stopover sites each species exhibited distinct habitat preferences. The timing of stopovers within sub-basins of the Amazon Basin also coincided with periods of low water, when the muddy, shallow water habitats preferred by most shorebirds are likely plentiful. Together, our results highlight the need for detailed investigations into shorebird abundance and distribution within the Amazon Basin, threats to shorebirds within particular subbasins, and links between shorebird conservation efforts and those targeting the myriad other species that inhabit this dynamic, hyper-diverse region.

Biotic and abiotic factors affecting Atlantic ghost crab (Ocypode quadrata) spatiotemporal activity at an important shorebird nesting site in Virginia.

Atlantic ghost crabs (Ocypode quadrata) are predators of beach-nesting shorebird nests and chicks on the United States' Atlantic and Gulf coasts. Ghost crabs may also disturb birds, altering foraging, habitat use, or nest and brood attendance patterns. Shorebird conservation strategies often involve predator and disturbance management to improve reproductive success, but efforts rarely target ghost crabs. Despite the threat to shorebird reproductive success, ghost crabs are a poorly understood part of the beach ecosystem and additional knowledge about ghost crab habitat selection is needed to inform shorebird conservation. We monitored ghost crab activity, defined as burrow abundance, throughout the shorebird breeding season on Metompkin Island, Virginia, an important breeding site for piping plovers (Charadrius melodus) and American oystercatchers (Haematopus palliatus). We counted burrows at shorebird nests and random locations throughout the breeding season and investigated whether ghost crab activity was greater at nest sites relative to random locations without shorebird nests. While we observed burrows at all nest sites (n = 63 nests), we found that burrow counts were lower at piping plover nests with shell cover, relative to random locations with no shell cover. Ghost crabs may avoid piping plover nest sites due to anti-predator behaviors from incubating adults or differences in microhabitat characteristics selected by piping plovers. We also investigated the effects of habitat type, date, and air temperature on the abundance of ghost crab burrows. We found that while crab burrows were present across the barrier island landscape, there were more burrows in sandy, undisturbed habitats behind the dunes, relative to wave-disturbed beach. Additionally, ghost crab activity increased later in the shorebird breeding season. Understanding when and where ghost crabs are most likely to be active in the landscape can aid decision-making to benefit imperiled shorebird populations.

Identifying shorebird conservation hotspots and restoration gaps in stopover sites: A perspective of ‘ecologically linked’ habitats

Shorebird populations are declining around the world, which has prompted concerns regarding tidal flat protection during migration. The lack of high-tide roosts not only can limit the access of shorebirds to tidal flats but also means that they expend more energy when moving between tidal flats and roosting sites. This situation can negatively affect their body condition. This highlights the importance of maintaining a network of tidal flats and high-tide roosts “ecologically linked” by shorebirds. Using the Yellow River Delta (YRD), a key stopover site in the East Asian–Australasian Flyway (EAAF), as the case study area, we assessed how the availability of optimal high-tide roosts has changed over time and identified conservation hotspots and restoration gaps from the perspective of ecological connectivity for shorebirds. Based on a developed Geographic Information System (GIS) method, combined with knowledge of shorebird roost choices from the literature and remote sensing data, we evaluated the adequacy of high-tide roosts in the YRD over 20 years (2000–2020) and identified restoration areas by scenario analysis. The results showed that 1) the mean distance between potential intertidal habitats and the nearest optimal high-tide habitat increased from 1305 m in 2000 to 2931 m in 2020, with a 30 % decline in the area of intertidal habitats suitably covered by optimal high-tide habitats for shorebirds in Group 1 (body length ≦ 20 cm) in the YRD; 2) the scenario analysis suggested that this gap can be eliminated by seasonal management of mariculture ponds and salt pans in key areas. This approach is likely applicable to stopover sites throughout the EAAF.

Nesting Habitat Suitability of the Kentish Plover in the Arid Lands of Xinjiang, China.

Understanding the main ecological factors of the nesting habitat of shorebirds is of great significance in relation to their protection and habitat management. Habitat loss and change due to a lack of water threaten the biodiversity of shorebirds, with impacts likely to be most pronounced in arid lands. We collected the data of 144 nesting sites and 10 ecological factors during the breeding season from April to July each year in 2019 and 2020 in nine river districts in Xinjiang. The MaxEnt model was applied to assess the suitability of nesting habitats for Kentish plovers (Charadrius alexandrinus) in the study area to examine the main factors affecting their nesting habitat. The most suitable nesting habitats are mostly distributed in plain reservoirs in the middle part of the Northern Slope of the Tianshan Mountains, Ebinur Lake and its eastern position in the southwestern Junggar Basin, near Ulungur Lake of the Ulungur river area and the southern Irtysh river area. The distance from water, normalized difference vegetation index, mean temperature of the breeding season, slope, and land use were the main factors affecting the nesting habitat selection of Kentish plovers. It was found that the proportion of suitable nesting habitat protected for the Kentish plovers in the study area was low (851.66 km2), accounting for only 11.02% of the total suitable nesting habitat area. In view of the scarcity and importance of water bodies in arid lands and the lack of protection for Kentish plovers at present, it is suggested to strengthen the conservation and management of the regional shorebirds and their habitats by regulating and optimizing the allocation of water resources.

Importance of habitat heterogeneity in tidal flats to the conservation of migratory shorebirds.

Understanding species distribution patterns and what determines them is critical for effective conservation planning and management. In the case of shorebirds migrating along the East Asian-Australasian Flyway (EAAF), the loss of stopover habitat in the Yellow Sea region is thought to be the primary reason for the precipitous population declines. However, the rates of decline vary considerably among species, and it remains unclear how such differences could arise within a group of closely related species using apparently similar habitats at the same locales. We mapped the spatial distributions of foraging shorebirds, as well as biotic (benthic invertebrates consumed by migrating shorebirds) and abiotic (sediment characteristics) environmental factors, at a key stopover site in eastern China. Five of the six sediment characteristics showed significant spatial variation with respect to distance along the shoreline or distance from the seawall in the same tidal flat. The biomasses of four of the six most abundant benthic invertebrates were concentrated in the upper or middle zones of the tidal flat. The distribution patterns of all three focal shorebird species on the tidal flat were best explained jointly by this heterogeneity of sediment characteristics and invertebrate prey. These results suggest that the loss of tidal flats along the Yellow Sea, which is typically concentrated at the upper and middle zones, may not only reduce the overall amount of staging habitat, but also disproportionately affect the most resource-rich portions for the birds. Effective conservation of shorebird staging areas along the EAAF and likely elsewhere must consider the subtle habitat heterogeneity that characterizes these tidal flats, prioritizing the protection of those portions richest in food resources, most frequently used by focal bird species, and most vulnerable to anthropogenic threats. Article impact statement: Heterogeneity of tidal flats with respect to biotic and abiotic factors must be considered in shorebird conservation planning.

An annotated checklist of the avifauna of Karangadu mangrove forest, Ramanathapuram, Tamil Nadu, with notes on the site’s importance for waterbird conservation

Avifaunal inventories are crucial to the formulation of conservation and management strategies for habitats and species. An annotated checklist of the birds of the Karangadu eco-tourism area located in the Palk Bay in Ramanathapuram district of Tamil Nadu, was prepared. We listed a total of 107 species belonging to 18 orders and 40 families. Orders Charadriiformes, Suliformes, and Pelecaniformes dominated the habitat. Among the families, Scolopacidae (10 species) was dominant, followed by Ardeidae (9), and Laridae (8). In addition, the study also documented three globally ‘Near Threatened’ species: Painted Stork Mycteria leucocephala, Black-tailed Godwit Limosa limosa, and Black-headed Ibis Threskiornis melanocephalus. The observed frequency of the species was: 57% (61 spp.) common, 32.7% (35 spp.) uncommon, and 10.3% (11 spp.) rare. Categorization based on the residential status of birds revealed that 31% (33 spp.) were winter visitors, and one was a passage migrant (Rosy Starling Pastor roseus). These baseline data highlight the importance of Karangadu as an important site on the southeastern coast of India for migratory shorebird conservation priorities.

Distribution Modeling and Gap Analysis of Shorebird Conservation in Northern Brazil

Migratory shorebirds are currently at significant risk, with populations of multiple species dropping globally, often due to habitat disruption and loss. The coast of northern Brazil, along the states of Pará and Maranhão, encompasses one of the broadest expanses of shorebird overwintering habitat for many shorebird species in the Atlantic Americas Flyway. Delineating how current management protects shorebird habitat is an important first step to identifying gaps in protections that then need to be prioritized. Different frameworks of conservation decision-making, such as focusing on flagship, umbrella, or biodiversity, can be used to prioritize what habitat needs to be protected. Understanding the effects of these different conservation perspectives is key to making informed management decisions. Multiple dates of Landsat 8 imagery at different tidal stages were used to identify intertidal habitats for further analysis. MaxEnt species distribution models were derived for each species using remote sensing and landscape metrics, as well as point-count survey data collected during the winters of 2016 and 2017. Landsat 8 and Sentinel 2 image data were included as direct inputs to the model rather than interpreted and mapped first into different habitat types. The resulting Maxent models successfully delineated between presence and absence locations for five of the eight target shorebird species. The model outputs were combined to map the intertidal habitat covered under several different management scenarios. These scenarios included using red knots as a flagship species, semipalmated sandpipers as an umbrella species, and species richness as a metric of shorebird diversity. Slightly more than 25% of delineated intertidal habitat was found to be included within a designated Marine Extractive Reserve, with three major gaps in current protections identified. The flagship, umbrella, and biodiversity perspectives result in different prioritizations of these distinct locations. While umbrella and diversity approaches are successful at protecting diverse communities, community assemblages of rarer or specialist species, such as the red knots, may fall outside their protective shadows. A hybrid approach that uses both diversity and the extent of rare flagship species produces results that best meet the management goals of identifying gaps in existing conservation to protect the most at-risk species while conserving the diverse assemblages they coexist with.

Shorebird food energy shortfalls and the effectiveness of habitat incentive programs in record wet, dry, and warm years

AbstractPrograms that incentivize private landowners to create habitats that offset losses due to conversion and climate change are increasingly being used to bolster sensitive wildlife populations. In the Central Valley of California, shorebird habitat incentive programs pay landowners to create additional habitat during the non‐breeding season by flooding their fields. However, it remains unclear how successful these programs have been in supporting baseline shorebird population needs or meeting established population goals, particularly in the face of changing environmental conditions. To address these questions, we used bioenergetics modeling to estimate shorebird food energy needs over four consecutive years that had the highest annual mean air temperatures ever recorded in California, and included years of extreme drought, as well as the second wettest winter on record. Our objectives were to (1) characterize annual variability in the timing and magnitude of shorebird food energy shortfalls, (2) estimate the contributions that incentive programs made to meeting these needs, and (3) develop recommendations for implementation of future habitat programs to advance shorebird conservation in the region. Overall, we found a high level of consistency in the timing and magnitude of habitat shortfalls, especially in fall, despite large differences in annual rainfall, a result that was unexpected, but that emphasizes how highly managed the hydrological system is in the Central Valley. We also found that the magnitude of both fall and spring energy shortfalls increased, relative to recent (2007–2014) estimates, perhaps due to aberrantly warm conditions. Incentive programs implemented to provide supplemental habitat were somewhat effective in reducing shortfalls for the assumed baseline population, but there were consistent unmet habitat needs when there were not enough shallow open water foraging areas available. Strategies to offset these remaining food energy deficits include scaling up habitat investments, adjusting the timing of habitat programs to better match the migration patterns of the birds, and adapting programs to new geographies. To the extent that there is variability in annual habitat need we recommend implementing a dynamic conservation approach. This involves scaling the amount of additional habitat created to match the shifting needs of the birds to maximize return on investment.

An emerging coastal wetland management dilemma between mangrove expansion and shorebird conservation.

Coastal wetlands around the world have been degraded by human activities. Global declines in the extent of important habitats including mangroves, salt marsh and tidal flats necessitate mitigation and restoration efforts, however some well-meaning management actions, particularly mangrove afforestation and breakwater construction, can inadvertently cause further loss and degradation if these actions are not planned carefully. In particular, there is a potential conflict between mangrove and shorebird conservation, because mangrove afforestation and restoration may occur at the expense of bare tidal flats, which form the main foraging habitats for threatened coastal migratory shorebirds as well as supporting other coastal organisms. Here, we present several case studies that illustrate the trade-off between mangroves and bare tidal flats. To investigate whether these examples reflect an emerging broad-scale issue, we use satellite imagery to develop a detailed quantification of the change in mangrove habitat extent in 22 important shorebird areas in mainland China between 2000 and 2015. Our results indicate that 1) the extent of mangroves across all sites expanded significantly between 2000 and 2015 (p < 0.01, n = 14) while tidal flat extent in the same areas declined significantly within the same period (p < 0.01, n = 21); 2) among the 14 sites where mangroves were present, the dual threat of mangrove expansion and tidal flat loss have considerably reduced shorebird habitat in eight of these sites. To ensure effective conservation of both mangroves and shorebirds, we propose a decision tree framework for resolving this emerging dilemma between mangrove afforestation and shorebird protection, which requires careful consideration of alternative management strategies. This article is protected by copyright. All rights reserved.

Occurrence and Behaviour of Shorebirds Depend on Food Availability and Distance of Beaches from Urban Settlements

Coastal ecosystems provide important feeding opportunities for shorebirds, depending on their prey availability, hydrodynamic conditions and human pressure. We aimed to evaluate short-term responses (occurrence and minimum approach distance) of shorebirds to urbanization and natural drivers on an extensive beach arc adjacent to the largest hypersaline coastal lagoon of South America. The presence of the migrant Sanderling Calidris alba and resident Collared Plover Charadrius collaris was geo-coordinated and for each record and an equivalent number of random points we measured the distance from urban settlements, swash width and invertebrate abundance (food availability) in a snapshot sampling. The distance at which each shorebird flock escaped from humans was determined (minimum approach distance). The occurrence of shorebirds was predicted by food availability, and higher crustacean density was found in areas of shorebird occurrence (37 ± 19 individuals/m2) compared to random points (10 ± 10 individuals/m2). This result highlights the importance of the beach as a feeding area and the need for conservation of shorebirds' prey. The resident Collared Plover delayed their escape from humans in areas closer to urban areas, suggesting a higher tolerance to humans on disturbed beaches, where they can prioritize the food intake rather than vigilance. The larger flocks let the researcher get closer, corroborating the risk-dilution theory stating that flocking behaviour during foraging provides protection of birds from predators. In conclusion, our results showed that monitoring of sandy beaches based on shorebirds' presence and behaviour can be a reliable tool, especially close to coastal lagoons that constitute foraging sites for these charismatic species.

Ecocultural attributes are important components of perceptions of the importance of coastal beaches of conservation concern

Sandy beaches along coasts and bays are prime real estate for houses and condominiums, marinas, recreation, and tourism for people living in urban and suburban areas within a hundred km of coasts. Human encroachment and disturbance can be a determinant of success of animals in human-impacted systems, particularly shorebirds. Understanding perceptions of people visiting critical habitats can aid in conservation of shorebirds and associated ecosystems, as well as improving the human experience. This paper examines valuation of ecological resources and ecocultural attributes of visitors to 9 beaches on the New Jersey shore of Delaware Bay during a shorebird migratory stopover period. Ecocultural attributes are those cultural activities or experiences that require an intact ecosystem to be optimal, including activities of recreational, aesthetic or spiritual importance. Using a Likert scale, interviewees (N = 279) rated the importance of shorebirds and/or horseshoe crabs Limulus polyphemus, ambiance, existence, aesthetics, the beach itself, and recreational activities (photography, birding, and fishing) to the Bay and to their experience. Although shorebirds/crabs were rated as most important (mean rating well over 4.0 out of 5); ecocultural attributes (ambience, existence, aesthetics, the beach itself) were rated higher (rating well over 3) than recreation, hardcore or casual birding, photography (mean rating around 3) and fishing (rating less than 2). Although some ratings of these resources and attributes were positively correlated, many values for birds and/or crabs were not correlated with the ecocultural attributes. Women rated most resources and ecocultural attributes higher than did men, and older people rated them higher than younger interviewees. It was unexpected that the ecocultural attributes played so heavily in the attractiveness of the beach. The importance and implication of these findings are discussed for management and conservation of these beaches, including the importance of ecocultural resources within a context of local community involvement.

Cathemeral Behavior of Piping Plovers (Charadrius melodus) Breeding along Michigan’s Lake Superior Shoreline

Shorebirds commonly exhibit cathemeral activity and commonly forage throughout a 24 h period. Conservation of endangered shorebirds should then extend to protection at night, yet little data exists on overall time budgets of such species at night. The Great Lakes population of piping plovers (Charadrius melodus) is the smallest and most endangered, making each breeding pair an essential part of recovery. Intense monitoring of breeding individuals occurs during the daytime, yet we have little understanding of the time budgets of plovers at night. To gain better insight into the cathemeral behavior of plovers we recorded behaviors of 12 plovers from along Michigan’s Lake Superior shoreline during both day and night in 2018 with the use of a night-vision-capable camera, and compared time budgets of plovers between daytime and nighttime. Overall, piping plovers spent more time and a greater proportion of their time foraging at night and more time devoted to being alert during the day. These differences were especially evident during the chick rearing phase. Limited observations suggest that copulatory activity may also be more common at night. Likely, the threat of avian predation on this population drives the increase in nighttime foraging, despite decreased efficiency. Recognizing the importance of decreasing potential for disturbance during the night should be considered in future management strategies regarding the recovery of this endangered species.

Using Geolocator Data to Address Changes in Migration Patterns for Black Turnstone

AbstractBlack Turnstone is an obligate Pacific coast shorebird that is included as a “Species of High Concern” in both the U.S. and Alaska Shorebird Conservation Plans. Specific migration routes for this species are not well understood, which makes its recent disappearance at a major spring stopover site, northern Montague Island in Prince William Sound, Alaska, difficult to interpret. We tracked 23 Black Turnstones between breeding and wintering areas and examined migration timing, duration, and routes used. We identified two high-use regions during migration: 1) Cook Inlet/Shelikof Strait, Alaska, and 2) the Haida Gwaii Archipelago in British Columbia/Alexander Archipelago in southeastern Alaska. This second region was also an important wintering area. We found that northbound migration was longer than southbound (the reverse of what is often observed in shorebirds) and that staging behavior was primarily seen during northbound migration. No birds were tracked to northern Montague Island, and only a few individuals stopped anywhere in Prince William Sound. Alterations in patterns of spring herring spawn in Prince William Sound may be affecting the routes and stopovers used by Black Turnstones, and birds may be wintering farther north in recent decades due to warmer winter conditions. Additionally, the increasing availability and popularity of citizen science efforts like eBird has created a mechanism for disseminating observations from less accessible parts of the Black Turnstone range, a fact which may confound our understanding of whether migration routes for this species have changed over the last 30 years.

Migration and Wintering Locations of Breeding Eastern Willet (Tringa semipalmata semipalmata) in the Western Gulf of Mexico

Knowledge of the geographic linking of individuals or populations between different annual life cycle stages is essential for effective conservation decision making. The Willet (Tringa semipalmata) is composed of two distinct subspecies that are separated by breeding habitat in North America, with eastern Willets breeding in estuarine marshes along the Atlantic and Gulf Coasts and western Willets breeding in wet grasslands and prairies in the interior west of North America. We studied the migratory paths and wintering locations of Texas Gulf Coast breeding eastern Willets from 2015 to 2019 using light-level geolocators. Data analysis from 9 retrieved geolocators indicated that all birds departed Texas 5-26 July, made a 2–5-day flight, and arrived on the wintering grounds 8–30 July. All birds wintered on the Pacific coasts of Central and South America. In spring, the birds departed the wintering location 9–24 March, made a 3–4-day flight and arrived on the breeding grounds 12–27 March. These results are in contrast to previous work which showed that Atlantic breeding eastern Willets overwintered on the Atlantic coast in northern South America. This work has implications for shorebird conservation planning, which currently considers all Willets overwintering on the Pacific coast to be western Willets.

Mangrove planting strategies should consider the optimal ratio between the area of tidal flats and the area of mangroves

Many countries, including China, have increased new areas of mangrove plantations to reverse the decline in mangrove ecosystem functions. However, this has led to the intrusion of mangroves into many tidal flat areas, which are important habitats for shorebirds. A reduction in the available tidal flat areas will reduce the diversity of shorebirds, therefore bringing mangrove conservation into conflict with shorebird conservation. In fact, a certain area of mangroves is an indispensable element of shorebird habitat. Therefore, this study proposes the maintenance of a ratio between the area of tidal flats and the area of mangroves within a mangrove ecosystem which is optimal for both mangrove conservation and shorebird conservation. This study recorded data for shorebird distribution, areas of mangrove and tidal flats, and other relevant data for Guangdong Province, China. The ratios of tidal flat areas to mangrove areas within mangrove ecosystems were established and a mathematical model was applied to establish the relationship between shorebird diversity and abundance and the ratios of tidal flat areas to mangrove areas. The results showed that: (1) there was no significant correlation between mangrove area and shorebird richness (r = 0.176, p = 0.230)and abundance(r = 0.104,p = 0.481), whereas there was no significant correlation between tidal flat area and shorebird richness(r = 0.153, p = 0.299)and abundance(r = −0.063,p = 0.670); (2) the relationship between the ratios of tidal flats area to mangrove area [x] and shorebird richness [f(x)] and abundance [g(x)] satisfied the cubic function equation f(x) =0.106x3−2.147x2+11.269x(0.0265≤x ≤ 13.8100) (R2 = 0.714, P = 0.000),g(x)=0.008x3−0.189x2+1.124x (0.0265≤ x ≤ 13.8100) (R2 = 0.713, P = 0.000); (3) the appropriate value of x is 3.5662or 3.9785, and maintaining this ratio can reduce the conflict between mangrove conservation and shorebird conservation and promote the sustainable development of the mangrove ecosystem. This information can contribute to the sustainable development of mangrove planting management strategies at various scales and will be invaluable in assessing the effectiveness of existing mangrove management approaches.

Long-term count data demonstrate the regional significance of Bako-Buntal Bay, Malaysian Borneo, for wintering shorebird conservation

Long-term count data demonstrate the regional significance of Bako-Buntal Bay, Malaysian Borneo, for wintering shorebird conservation

Widespread use of artificial habitats by shorebirds in Australia

ABSTRACT Shorebirds in the East Asian-Australasian Flyway have experienced population declines linked to loss of coastal wetlands. Despite this vulnerability to habitat loss, shorebirds regularly use artificial habitats, especially for high-tide roosting. Understanding the distribution of shorebirds in artificial versus natural roosts could inform habitat management strategies aimed at population recovery. We analysed time-series of high-tide shorebird monitoring data from five developed regions of Australia where artificial habitat use has previously been documented and made three key discoveries. First, artificial habitat use was generally high across the regions, with >50% of the average proportion of the regional population of 39 of 75 species-region combinations (52%) using artificial habitats at high tide. Second, in 84% of species-region combinations the average proportion of birds that used artificial habitats from the time of their establishment onward did not show a significant temporal trend. Third, migratory and coastal specialist species showed lower proportional artificial habitat use than non-migratory and generalist/inland specialist species. These findings showing consistent, widespread use of artificial habitats by large shorebird aggregations at high tide suggest that a framework for high-tide habitat management that includes artificial habitats alongside preservation of remaining natural habitats could make a significant contribution to shorebird conservation in Australia.