Waterbird Breeding Research Articles

Factors Influencing Species-Richness of Breeding Waterbirds in Moroccan IBA and Ramsar Wetlands: A Macroecological Approach

Since 2005, Morocco has designated 28 Important Bird Areas (IBA) and Ramsar wetlands for waterbirds, yet little is known about how waterbird communities are changing over time and space, within and between sites. We assessed the relationships between species numbers of overall breeding waterbirds, as well as those of Anatidae, Rallidae and Podicipedidae, and geographical, topographical and macrohabitat factors. Species richness of overall waterbirds and Anatidae were positively correlated with: (i) extent of emergent vegetation, (ii) number of plant species present, and (iii) altitude. Species richness of Rallidae was positively correlated with: (i) latitude, and (ii) different beds of emergent vegetation, while that of Podicipedidae was exclusively correlated with altitude. These results suggest that breeding waterfowl are significantly related to habitat characteristics, most importantly vegetation structure, and altitude. Our findings give support to the idea that large mountain wetlands protected areas provide valuable habitat to breeding waterbirds in this region, by providing larger buffer zones with fewer human activities, such as hunting, urbanization and tourism disturbance. This study provides a platform from which we can advance the scientific research on Moroccan IBA and Ramsar wetlands.

Assessing climate change impacts on wetlands in a flow regulated catchment: A case study in the Macquarie Marshes, Australia

Globally wetlands are increasingly under threat due to changes in water regimes as a result of river regulation and climate change. We developed the Exploring CLimAte Impacts on Management (EXCLAIM) decision support system (DSS), which simulates flow-driven habitat condition for 16 vegetation species, 13 waterbird species and 4 fish groups in the Macquarie catchment, Australia. The EXCLAIM DSS estimates impacts to habitat condition, considering scenarios of climate change and water management. The model framework underlying the DSS is a probabilistic Bayesian network, and this approach was chosen to explicitly represent uncertainties in climate change scenarios and predicted ecological outcomes. The results suggest that the scenario with no climate change and no water resource development (i.e. flow condition without dams, weirs or water license entitlements, often regarded as a surrogate for ‘natural’ flow) consistently has the most beneficial outcomes for vegetation, waterbird and native fish. The 2030 dry climate change scenario delivers the poorest ecological outcomes overall, whereas the 2030 wet climate change scenario has beneficial outcomes for waterbird breeding, but delivers poor outcomes for river red gum and black box woodlands, and fish that prefer river channels as habitats. A formal evaluation of the waterbird breeding model showed that higher numbers of observed nest counts are typically associated with higher modelled average breeding habitat conditions. The EXCLAIM DSS provides a generic framework to link hydrology and ecological habitats for a large number of species, based on best available knowledge of their flood requirements. It is a starting point towards developing an integrated tool for assessing climate change impacts on wetland ecosystems.

Species Diversity, Abundance and Brood Numbers of Breeding Waterbirds in Relation to Habitat Properties in an Agricultural Watershed

Land-use changes and the resulting habitat degradation have been regarded as the most important known causes of waterfowl population declines. We assessed the habitat requirements of waterbirds, including waterfowl, in a hemiboreal, agricultural watershed in southern Finland. We related the birds' species diversity, abundance and brood numbers on ten lakes to environmental variables, including land use characteristics as well as topographic and local biotic features. Both species diversity and pair numbers responded to land use characteristics, such as the area of agricultural land surrounding the lakes. Our results suggest that land use may reflect habitat quality, possibly in terms of resource availability and predation risk. The pair numbers of waterbirds grew along with the availability of invertebrates, an important food resource. The abundance of gulls affected the diversity, abundance and reproductive success of waterfowl positively in our study area, probably because they provided shelter from pre...

Urban wetland parks in Finland: improving water quality and creating endangered habitats

Urbanization changes water balance, degrades water quality and disrupts habitats. Wetlands offer storm water volume and flow control, water pollution mitigation, and rich land–water interphase habitats. In the present case study, urban wetlands were designed and implemented to provide multiple functions, including water quality improvement and the establishment of critically endangered clay stream habitat, along a revived urban stream within the Baltic Sea watershed in Southern Finland. The primary water quality concern in the recipient lake is algal bloom controlling and clay particle-carried phosphorus.Wetlands were monitored for functioning over five calendar years. At a wetland monitored for 5 years, herbaceous vegetation was well self-established in the second year, and reached 102 species, of which 97% were native, in the fifth growing season. Successful breeding of amphibians and water birds occurred right after construction. Continuous water quality monitoring over the fourth year at this wetland, with 0.1% area of its watershed, revealed seasonal and event-based differences: for total phosphorus, an annual 10% average with lower removal rates outside, and up to 71% event reductions during the growing season, while highest load reductions occurred during heavy rain and snowmelt events outside the growing season. The created wetlands provided critical habitat and beneficial functions and thus compensated partly for urbanization.

Skjern River Valley, Northern Europe’s most expensive wetland restoration project: benefits to breeding waterbirds

After circa 35 years of drainage and intensive arable tillage, the lower Skjern River, Den-mark was re-engineered to its original meanders and flooding regime, creating 22 km 2 of lakes, shallow wetlands and seasonally flooded grazed wet grassland costing €38 million. The primary motivation was to restore the sediment/nutrient retention capacity of the river valley to reduce eutrophication of Ringkøbing Fjord at its efflux. Secondary objectives were to (i) restore breeding and staging bird habitat, (ii) enhance the self-sustaining Atlantic Salmon Salmo salar population and (iii) improve recreational and tourist activities. Despite lack of specific success criteria, breeding waterbird numbers increased from 134 ± 22.9 SE (n = 3) pairs before to 1,744 ± 153 SE (n = 5) after restoration (although on average 1,004 of these were Black-headed Gulls Chroicocephalus ridibundus), species richness and diversity also increased. Twenty-nine waterbird species returned to breed, 10 of national or international significance (Danish Red List/European Union Birds Directive Annex 1 species) now ranking Skjern River amongst the top 10 most important breeding waterbird sites in Denmark. Currently, agriculture supports cost-neutral management of the restoration area, but whilst most expected wet meadow and marsh species had returned, lack of goal-orientated management targets resulted in some additional rare and threatened species remaining absent. Breeding pair density and diversity of other species could have been greatly improved by prior planning and management intervention but at additional cost.

Forster's tern chick survival in response to a managed relocation of predatory California gulls

ABSTRACTGull populations can severely limit the productivity of waterbirds. Relocating gull colonies may reduce their effects on nearby breeding waterbirds, but there are few examples of this management strategy. We examined gull predation and survival of Forster's tern (Sterna forsteri) chicks before (2010) and after (2011) the managed relocation of the largest California gull (Larus californicus) colony (24,000 adults) in San Francisco Bay, California. Overall, survival of radio‐marked Forster's tern chicks from hatching to fledging was 0.22 ± 0.03 (mean ± SE), and daily survival rates increased with age. Gulls were the predominant predator of tern chicks, potentially causing 54% of chick deaths. Prior to the gull colony relocation, 56% of radio‐marked and 20% of banded tern chicks from the nearest tern colony were recovered dead in the gull colony, compared to only 15% of radio‐marked and 4% of banded chicks recovered dead from all other tern colonies. The managed relocation of the gull colony substantially increased tern chick survival (by 900%) in the nearby (<1 km) colony from 0.04 ± 0.02 in 2010 to 0.40 ± 0.12 in 2011 but not at the more distant (>3.8 km) reference tern colony (0.29 ± 0.10 in 2010 and 0.25 ± 0.09 in 2011). Among 19 tern nesting islands, fledging success was higher when gull abundance was lower at nearby colonies and when gull colonies were farther from the tern colony. Our results indicate that the managed relocation of gull colonies away from preferred nesting areas of sensitive waterbirds can improve local reproductive success, but this conservation strategy may shift gull predation pressure to other areas or species. © 2014. This article is a U.S. Government work and is in the public domain in the USA.

Vulnerability of breeding waterbirds to climate change in the Prairie Pothole Region, U.S.A.

The Prairie Pothole Region (PPR) of the north-central U.S. and south-central Canada contains millions of small prairie wetlands that provide critical habitat to many migrating and breeding waterbirds. Due to their small size and the relatively dry climate of the region, these wetlands are considered at high risk for negative climate change effects as temperatures increase. To estimate the potential impacts of climate change on breeding waterbirds, we predicted current and future distributions of species common in the PPR using species distribution models (SDMs). We created regional-scale SDMs for the U.S. PPR using Breeding Bird Survey occurrence records for 1971–2011 and wetland, upland, and climate variables. For each species, we predicted current distribution based on climate records for 1981–2000 and projected future distributions to climate scenarios for 2040–2049. Species were projected to, on average, lose almost half their current habitat (-46%). However, individual species projections varied widely, from +8% (Upland Sandpiper) to -100% (Wilson's Snipe). Variable importance ranks indicated that land cover (wetland and upland) variables were generally more important than climate variables in predicting species distributions. However, climate variables were relatively more important during a drought period. Projected distributions of species responses to climate change contracted within current areas of distribution rather than shifting. Given the large variation in species-level impacts, we suggest that climate change mitigation efforts focus on species projected to be the most vulnerable by enacting targeted wetland management, easement acquisition, and restoration efforts.

Annual Changes in Fecal Sex Hormones with Corresponding Changes in Reproductive Behaviors in Thai Sarus Crane, Black-headed Ibis, and Lesser Adjutant Stork

We monitored annual fecal sex hormones and reproductive displays of five individuals of males and females Thai sarus crane (Grus antigone sharpii), a flock of five males and females black-headed Ibis (Threskiornis melanocephalus), and five pair bonded lesser adjutant stork (Leptoptilos javanicus), all maintained in captivity at Bangprha Waterbird Breeding Research Center. Reproductive behaviors were observed during 0600-1800 h, for four days during the second week of each month and feces were collected monthly to determine annual male total testosterone (mTT) and female estradiol (fE2) levels by radioimmunoassay. Thai sarus crane exhibited a peak mTT in August following a fE2, with a surge in July. Black-headed ibis demonstrated a peak mTT in January prior to a fE2 with a surge in March. Lesser adjutant stork showed a maximal mTT coincidently with fE2 with a surge in October. Thai sarus crane frequently displayed courtship in May-October, corresponding well with higher mTT rather than fE2 levels. Black-headed ibis showed courtship-copulation displays in January, simultaneously with mTT, but not with fE2 surge. Lesser adjutant stork often displayed courtship-copulation in October-January, seemingly corresponded with higher mTT and fE2 levels during October-December and October-November, respectively. Male and female lesser adjutant stork displayed egg-incubation and chick-rearing behaviors in November-January and December-June, respectively. We suggest that mTT and/or fE2 apparently played an important role in regulation of courtship-copulation displays but did not relate to both egg-incubation and chickrearing behaviors.

Development and cross-species transferability of 23 microsatellite markers from the vulnerable Chinese Egret (Egretta eulophotes) using 454 sequencing

The Chinese Egret (Egretta eulophotes) is a vulnerable waterbird breeding on offshore islands. Here, 23 new microsatellite loci were isolated using 454 pyrosequencing, and were tested in 32 individuals from a single population in Fujian province of China. The number of alleles per locus ranged from 2 to 9. Observed heterozygosity and expected heterozygosity ranged from 0.094 to 0.844 and 0.091 to 0.840, respectively. All loci showed Hardy–Weinberg equilibrium with the exception of three loci (Ee10, Ee17 and Ee23), possibly because of null alleles. The new loci also were confirmed a high cross-amplification success rate in the other seven Ardeid species. These new microsatellite data will provide a major resource for future conservation genetics studies on this vulnerable egret and the other Ardeids.

Short-Term Demographic Responses of a Coastal Waterbird Community After Two Major Hurricanes

Abstract. Response of breeding waterbird communities to the effects of hurricanes remains poorly understood. The impact of two 2008 hurricanes on the breeding waterbird community was investigated at the Isles Dernieres Barrier Island Refuge in southern Louisiana using pre- and post-hurricane survey data. After the 2008 hurricanes, the breeding community was reduced from 44,042 breeding pairs in 2008 to 27,977 pairs in 2009 and to 23,544 pairs in 2010. Populations of the five most abundant species, Brown Pelican (Pelecanus occidentalis), Laughing Gull (Leucophaeus atricilla), Royal Tern (Thallasseus maximus), Sandwich Tern (Thallasseus sandvincensis), and Black Skimmer (Rynchops niger), decreased from 2008 to 2010. In contrast, populations of Roseate Spoonbill (Platalea ajaja), Sooty Tern (Onychoprion fuscatus), and Gull-billed Tern (Gelochelidon nilotica) increased from 2008 to 2009 but declined in 2010. The dramatic decline of total breeding pairs in the year following hurricanes demonstrates the vulnera...

Significant Impacts of the Water Level and Human Intervention on the Natural Habitats and Breeding Waterbirds in Marmara Lake

Habitat cover and change were analysed in the Marmara Lake to investigate the effects of water level and human intervention on the natural habitats and breeding waterbirds. Breeding Birds Surveys were applied to investigate breeding waterbirds and their breeding activities in 2008 and 2011. GIS, remote sensing techniques and various satellite images were used to determine distributions, surface areas, zonal centroids, and displacements of the habitats in 2000, 2008 and 2011. The total number of bird species with and without breeding evidence in 2008 and 2011 were compared with the Chi-Square test. Habitats in each UTM grid in 2008 and 2011 were compared with McNemar’s test. The impact of water level on habitats, number of breeding birds, and their breeding parameters were investigated using Spearman’s correlation analyses. The major habitats were open waters, reed beds, scrubs and woodlands, wet grasslands, and mudflats. Significant increases were observed in open waters, reed beds, and wet grasslands, but no significant change was observed for scrubs and woodlands. Out of 70 UTM grids, 69 and 48 grids corresponding to 95 and 75 observation points were surveyed in 2008 and 2011, and 34 different waterbirds were identified. The total number of breeding waterbirds significantly increased in 2011. Open waters were positively correlated with reed beds and negatively correlated with mudflats. Among 34 waterbird species, changes in the breeding parameters of 22 species were significantly correlated with the changes occurring in the major habitats. Our study demonstrates that changes in water level significantly affected the existence of key habitats and theirs distributions, resulting in significant changes in the number of breeding waterbirds and their breeding activities.

Impacts of anthropogenic activities and habitat degradation on breeding waterbirds

We investigated the effects of threats on breeding waterbirds in the Gediz Delta, Turkey. Breeding Bird Surveys were conducted in 2002 and 2006. The survey area comprised 305 UTM grids of 1 × 1 km^2. Populations and distributions of breeding birds were compared between 2002 and 2006 for the UTM grids under threat and without any threat using paired samples t-test, Wilcoxon signed-rank test, and GIS. Urbanization, industrialization, pollution, overgrazing, disturbance, and illegal reed cutting and burning were identified in 151 (49.5%) of 305 grids in 2002. The mean total number of breeding birds per UTM grid slightly decreased in areas under threat, but significantly increased (P < 0.05) in areas without threat. The mean total number of breeding waterbirds significantly decreased (P < 0.05) in both the grids under and without threat. Out of 30 waterbirds breeding in grids under threat, 23 shifted their breeding locations. The total number of breeding pairs of 9 waterbirds decreased, 7 species increased, and 6 species were stable. The maximum breeding code of 6, maximum number of breeding pairs of 11, total number of observed birds of 11, and frequency of occurrence of 15 species significantly decreased in UTM grids under threat. Threats have significantly affected (P < 0.05) the breeding populations of bird species even in a short period of 4 years.

Birds Observation and Nest Count of Crab Plover &lt;i&gt;Dromas ardeola&lt;/i&gt;, Western Reef Heron &lt;i&gt;Egretta gularis&lt;/i&gt; and four Tern species on Ghaber Nakhoda Island (Persian Gulf) in 2003 and 2012

This research was conducted in Ghabre Nakhoda Island (30°20′26″ N 48°55′53″ E) in Khore mosa Creek from May 2003 to December 2003 and May 2012 to December 2012. The area of the island is about 3 hectare. The aim of this study is to provide a complete picture of the Present population of the colonial breeding waterbirds in Ghabre Nakhoda island in Khore Mosa Creek. Total count method was used to obtain the census of the nests and breeding population. Thirty tow species of waterbirds were identified in the island, of which eight species were breeder. Lesser Crested Tern Sterna bengalensis was dominant and indicates. The maximum breeder population of this species was 2500 pairs in 2003. Other breeder species were Crab Plover Dromas ardeola , Lesser Crested Tern Sterna bengalensis , Swift Tern Sterna bergii , Caspian Tern Sterna caspia , Bridled Terns Sterna anaethetus , Western Reef Heron Egretta gularis , and a small colony of White cheeked Tern Sterna repressa . The island has been identified as an Important Bird Area by Birdlife international proposed for protection as a part of the Shadeghan wildlife refuge and suggested for to be classified as sensitive habitat for breeding waterbirds. The main plant communities of the island are Atriplex sp, Stipa sp, Suaeda sp. and Halostachys sp..

Census and Phenology of Breeding Waterbirds on the Islands of Khan, Tahmadon, Om-Al-Gorm and Nakhiloo in the Persian Gulf, Iran

There are 4 islands Khan, Tahmadon, Om-Al-Gorm and Nakhiloo in the Mond Protected in Boshehr province in the Persian Gulf. This research was conducted in these islands from March 2008 to September 2012. Thirty four species of birds were identified in these Islands. Nine species were breeders. Bridled Tern Sterna anaethetus was dominant and indicates. The maximum population of this species was 29,461 pairs in 2006 in Nakhiloo. The Maximum breeding population of Lesser Crested Tern Sterna bengalensis was 11,783 pairs in 2012 in Nakhiloo, and Swift Tern Sterna bergii was estimated at 2,500 pairs in 2008. We estimated 92 pairs of Western Reef Heron Egretta gularis and 2,825 pairs of Crab Plover Dromas ardeola in 2005 in Om-Al-Gorm. The other breeders were Caspian Tern Sterna caspia , Gull-billed Tern Sterna nilotica , White-cheecked Tern Sterna repressa and Saunders’s Tern Sterna saunders . These four islands are the most important and sensitive habitat for breeding terns species Sterna sp, Crab Plover Dromas ardeola and Western Reef Heron Egretta gularis in the Persian Gulf. The islands have been identified as an Important Bird Area by Birdlife International proposed for protection as a part of the Mond Protected Area, now part of National Marine Park of Dayer, and suggested for to be classified as sensitive habitat for breeding seabirds.

Strong seasonal effects of waterbirds on benthic communities in shallow lakes

Little is known about the effects of waterbirds on benthic macroinvertebrates in nontidal habitats. We conducted 4 waterbird-exclusion experiments in a transformed marshland in Doñana Natural Park (southwestern Spain) and compared benthic macroinvertebrates in 3 × 3-m control (no exclusion) and test plots from which Greater Flamingos Phoenicopterus ruber or all waterbirds were excluded. The 4 experimental periods coincided with the waterbird breeding season (summer), postbreeding period (autumn), wintering period (winter), and pre- and early breeding season (spring). Densities of waterbirds were relatively low compared to densities reported in other studies, but we found strong effects of excluding flamingos and waterfowl on the structure of the benthic community in autumn, winter, and spring. In winter, numbers of polychaetes and chironomids were nearly 2× higher in exclusion than in control plots. The difference in macroinvertebrate biomass among treatments was strongest in winter when benthic dry mass was ∼2× higher in flamingo exclosures than in control plots and ∼2× higher in all-bird exclosures than in flamingo exclosures. Macroinvertebrate richness was 15% lower in control than in all-bird exclosures in winter and 25% lower in control than in all-bird exclosures in spring. Our results suggest that benthic macroinvertebrate communities in this wetland are affected more by predation, bioturbation, and waterbird herbivory than by competition. These findings suggest that waterfowl and the increasing population of flamingos are of great importance in structuring shallow lakes in the Mediterranean region.

The Distribution of Colonial Waterbirds in Relation to a Ugandan Rice Scheme

The study aim was to describe and explain the distribution of waterbird breeding colonies in the vicinity of one of Uganda's largest rice schemes, Doho, a major feeding site for waterbirds. A total of 18 colonies were identified in which six species bred and two others were found roosting. Colony size ranged from seven to 588 breeding pairs. All colonies were located within human settlements, contrasting with patterns seen in typical waterbird colonies in Europe and America. Seventy-five percent of waterbirds placed their nests on Mvule trees (Milicia excelsea) while the number of breeding pairs was positively correlated to the number of trees at colonies. Contrary to expectations, colony size was not correlated with distance from the Doho rice scheme, or with the amount of foraging area within one, five and 10 km from the colony. These results suggest that nesting, rather than foraging habitat could be restricting the distribution and potentially population sizes of tree-nesting waterbirds in our study area. They also highlight the importance of the Mvule as nesting habitat for waterbirds, a tree species that is in great need of protection throughout Uganda, and presumably throughout other parts of Africa.

Hunting and the fate of French breeding waterbirds

Capsule French breeding populations of hunted waterbirds have more negative long-term population trends than closely related non-hunted species. Aims To assess the relative fate of breeding populations of hunted and non-hunted waterbird species in France. Methods We compared long-term population growth rates of hunted versus non-hunted waterbirds using two large-scale and long-term national surveys. Results Waterbirds globally displayed long-term increases in population sizes most likely driven by their positive response to the implementation of numerous protected areas over remnant wetlands across the country since the early 1970s. In contrast, hunted species revealed more negative trends compared to non-hunted species. Conclusion A causal relationship between hunting and population dynamics is not demonstrated here, but the results are consistent with species' breeding populations being negatively affected, on average, if they are hunted.

МАТЕМАТИЧЕСКИЙ АНАЛИЗ ДИНАМИКИ ЧИСЛЕННОСТИ НЕКОТОРЫХ ОКОЛОВОДНЫХ ВИДОВ ПТИЦ ОСТРОВОВ СИВАША

&lt;p&gt;The problem of the mathematical analysis of dynamics of number of key colonial breeding waterbirds regarding to the islands of region is considered. The algorithm of an estimation of changes in number of birds is offered in scope of specific features of colonies and habitats. The data of long-term monitoring of island birds’ number have been analyzed according to proposed algorithm. On the basis of analysis results the necessity of use of the statistical indexes expressing the tendencies of changes in bird number and bird turnover is proved. For the key species of island communities the tendencies of changes in number are determined within the limits of researched region. The discussed technique of a complex estimation of breeding island bird dynamics is offered for the use at drawing up the management plans and development of nature protection actions with the purpose of conservation of bird diversity and their habitats.&lt;/p&gt; &lt;p&gt;&lt;em&gt;Key words: colonial birds, islands, dynamics of number, complex estimation&lt;/em&gt;&lt;/p&gt; &lt;p&gt; &lt;/p&gt;

Breeding Flow Thresholds of Colonial Breeding Waterbirds in the Murray-Darling Basin, Australia

Biodiversity on floodplains is under increasing pressure as demand for water for human needs expands. Understanding how waterbirds respond to river flows feeding floodplain wetlands is critical for successful management. We analysed data on breeding by colonial breeding large waders—Eastern Great Egret Ardea modesta, Intermediate Egret Ardea intermedia, Little Egret Egretta garzetta, Nankeen Night Heron Nycticorax caledonicus, Australian White Ibis Threskiornis molucca, Glossy Ibis Plegadis falcinellus, Straw-necked Ibis Threskiornis spinicollis, and Royal Spoonbill Platalea regia—in response to river flow for three wetlands in the Murray-Darling Basin, Australia. Each wetland, which included Barmah-Millewa, the Macquarie Marshes, and Lake Merreti, has a distinctive geomorphology and hydrology. There were clear consistent thresholds of flow producing a >0.7 probability of attempted breeding by most species when a daily flow threshold was exceeded for 30–50 days. Flow characteristics were highly correlated and thresholds could also be expressed in terms of the total flow volume July–December and peak flow in September or October. Below thresholds, there was zero probability of breeding for most species. These minimum thresholds provide critical information for management of these wetlands. Our approach provides an analytical framework for estimating thresholds for other floodplains.

High resolution species distribution models of two nesting water bird species: a study of transferability and predictive performance

Species distribution modelling is increasingly used in ecological studies and is particularly useful in conservation planning. Models are, however, typically created with a coarse resolution, although conservation planning often requires a high resolution. In this study we created high resolution models and explored central aspects of the modelling procedure; transferability and predictive performance of the models. We created models for two breeding water bird species, common eider Somateria mollissima and herring gull Larus argentatus, based on data from two regions in the Finnish archipelago (234 islands). We used seven variables which we considered as potential predictors of nest site location: distance to forest, distance to rock and distance to low vegetation, exposure, elevation, slope and curvature of the land surface. We tested the predictive ability of the models crosswise between the areas by using area under the receiver operating characteristic curve. The models were transferable between our study areas and the predictive performance varied from fair to excellent. The most important predictors overall were exposure and distance to forest. More general models, with higher regularization values in the Maxent software, had better transferability regarding predictive performance. However, when we fitted a model based on 60% of the data from both regions and evaluated the model on the remaining 40%, the most complex model had the highest accuracy. Extrapolation of SDMs, evaluated on data from the same region, should therefore always be done with caution as the most accurate model might not have the best transferability if it is not general enough.