Invasive species

Parental Behavior Linked to Declining Nest Success

New Red-billed Tropicbird data suggested declining nest survival rates may be more related to parental behavior than previously thought. A researcher from Utrecht University, along with STENAPA and CNSI staff analyzed nest characteristics, trap camera photos and historical data to better understand the driving factors to declining nest survival rates.

Seabird populations are facing unprecedented levels of threats which has resulted in nearly 70% loss of monitored seabird populations over the past fifty years.  This is faster than any other group of birds worldwide and can be linked to overfishing, habitat destruction, invasive species, increased storm events and changes in food availability.

Red-billed Tropicbird and chick. Photo credit: Michiel Boeken

Pilot Hill

The Red-billed Tropicbird are an iconic species for the northern Dutch Caribbean islands.  In fact, a small but globally significant colony of breeding pairs nests within the Boven Important Bird Areas of Sint Eustatius.  Unfortunately, this area has been experiencing high rates of nest failure over the past decade. New research, conducted by Utrecht University student Hailley Danielson-Owczynsky, analyzed a combination of previously collected information with new monitoring data from the Pilot Hill nesting area in an attempt to better understand what is causing these low success rates.

Nest Monitoring

Previously, high predation by cats, rats and crabs were blamed for declining egg survival rates.  This was partially linked to the success of predator control projects on Saba, where nest survival of one site was improved from 0 to 40% after two-seasons of cat removal. Additionally, when reviewing the 1.6 million photos taken by nest cameras between 2017 and 2022, 80.5% of monitored nests showed predator presence, leading managers to blame predators for declining numbers. Further analysis conducted by Danielson-Owczynsky found that before being consumed by predators, many of the eggs had already been left unattended by parents for a prolonged period of time.  This same study found that predators were much less likely to visit a nest when a parent was nearby. Therefore, egg failure is more likely attributed to parent behavior prior to its predation.  It is important to note that invasive predators are still a concern, these results merely give an additional factor for conservation managers to consider.

Difficult foraging conditions for Tropicbird parents could lead to decreased nest attendance.  Red-billed Tropicbird’s diet is comprised primarily of flying-fish; however, overfishing has led to a decrease in overall fish populations requiring parents to forge over greater distances for longer periods of time.

Red-billed tropicbird. Photo source: Christian König

Implications

Pelagic seabirds, such as the Red-billed Tropicbird possess many unique traits, such as long lifespans, slow development and low reproductive rates, often attributed to their limited and sporadic food supply.  Given their long-life spans and the fact that they forage across wide ranges, these birds have been used as indicators for overall marine ecosystem health.  Therefore, the rapid decline in local populations gives key insight and rising concern for overall marine environmental conditions.  Understanding the magnitude of threats facing these and other related species will be key in safeguarding a strong and resilient marine environment moving forward.

 

Report your sightings

Species reports by local communities and tourists are invaluable for nature conservation efforts to help increase public awareness and overall species protection.

You can report your Red-billed Tropicbird sightings and photos on the website www.Observation.org or download the free apps (iPhone (iObs) & Android (ObsMapp)). You can also send your information to research@DCNAnature.org for support. An automatic species recognition tool is in development, so stay tuned for updates.

 

To learn more, you can find the full report by using the link below.

More info in the Dutch Caribbean Biodiversity Database

 

 

Published in BioNews 56.

Date
2022
Data type
Media
Theme
Research and monitoring
Geographic location
St. Eustatius
Author

Protecting Fish Proven Key in Slowing Down Invasive Seagrass

New research from Wageningen University, University of Amsterdam and Florida International University highlighted the role herbivorous fish species plays in staving off nonnative seagrass invasions.  A healthy and diverse fish population can provide top-down control by grazing on invasive seagrass species, minimizing its overall invasion.

Invasive species can pose a direct threat to native species through competition and hybridization. Species which evolved to reproduce and spread rapidly generally have a greater chance at survival, and when introduced to a new environment, can out compete slower growing native species. This is certainly the case for Halophila stipulacea, a seagrass native to the Red Sea, Persian Gulf and Indian Ocean which has been rapidly gaining habitat within the Caribbean since its first reported sighting in 2002. This species is quickly outpacing native Thalassia testudinum (turtle grass) and Syringodium filiforme (manatee grass), both of which provide critical habitat, coastal protection and foraging grounds. 

 

Mixed area of Halophila stipulacea (shorter blades) and Thalassia testudinum (longer blades). Photo Credit: Fee Smulders

The Study

A new study by Wageningen University and Research, the University of Amsterdam and Florida International University worked to improve overall understanding of the controlling factors in the spread of invasive seagrasses.  Researchers investigated the influences of local nutrient enrichment (nitrogen and phosphorus) as well as the impact of large herbivorous fish on the growth and expansion rates of Halophila stipulacea. The study took place between 2018 and 2019 within two seagrass meadows, Lac Bay on Bonaire and Barcadera on Aruba.

Seagrass Meadow. Photo Credit: Fee Smulders

The Results

At both sites, nutrients were added to selected seagrass plots by using slow-release fertilizer. Interestingly, only on Bonaire did these excess nutrients actually result in a reduction of H. stipulacea’s expansion into the turtle grass meadows, while native seagrass was unaffected.  This is believed to be because on Bonaire, herbivore fish abundance is 7 times greater and diversity is 4.5 times higher than on Aruba, therefore excess nutrients likely enticed more fish to graze therefore limiting the spread of the invasive seagrass.  Native seagrass is more adapted to high grazing pressures, during this study grazing pressure increased after nutrient enrichment but only the invasive species showed lower expansion rates.  In fact, the exclusion of large herbivorous fish (like parrotfish) doubled the invasive expansion rates within sandy patches on Bonaire, further strengthening this theory.

Top-Down Approach

This study highlights the importance of holistic approaches to ecosystem management.  Healthy and diverse fish communities can provide top-down control to invasive species expansion Increasing grazing pressures can help reduce the competitive advantage of fast-growing species, slowing down invasion of non-native species. The key to seagrass restoration and conservation could lie in protecting the biodiversity of these fragile areas.

To learn more, please find the full report on the Dutch Caribbean Biodiversity Database using the button below.

https://www.dcbd.nl/document/fish-grazing-enhanced-nutrient-enrichment-m...

 

Article published in BioNews 49

Date
2021
Data type
Media
Theme
Education and outreach
Research and monitoring
Geographic location
Aruba
Bonaire
Author

Using Satellite Imagery to Map St. Eustatius Coralita Invasion

Coralita is an invasive plant species, rapidly spreading across St. Eustatius.  A recently published report highlighted the ability to use satellite imagery to systematically map Coralita’s distribution over the island.  The approach could provide key insights into how habitat and vegetation are changing over time to aid in conservationists’ efforts to minimize the negative effects of Coralita and similar invasive species.

Coralita overgrowth (Source: Achsah Mitchell)

Coralita is a fast-growing, climbing vine with beautiful pink or white flowers. Originally from Mexico, Antigonon leptopus started out as a popular garden plant, but has expanded its territory and is now aggressively invading natural areas. Its fast-growing nature means it can outcompete most native species for terrain, quickly making it the dominant species, and reducing overall diversity. This is especially the case on St. Eustatius, where ground surveys indicate the plant already appears on 15-33% of the island.

Mapping Techniques

One of the biggest issues in controlling invasive species is accurately accounting for its presence, particularly if data needs to be collected over a wide area. This is where satellite imagery can help by providing an affordable, high spatial resolution option. A new collaborative study from the Utrecht University, University of Zurich, Wageningen University, and the Technical University of Braunschweig provided key insight by using such satellite imagery to identify Coralita. The method is successful, as areas dominated by Coralita emit a relatively distinct electromagnetic signal that can be detected by satellites. Once the distribution of Coralita has been mapped using this technique, it is possible to identify the environmental conditions associated with Coralita’s presence. This approach provides a relatively low-cost solution that is powerful, accurate and repeatable; key in identifying and monitoring its spread in the future.

“In creating this map,” said Elizabeth Haber, first author of this study, “it was my hope to produce something that could be useful for those who are caring for and protecting the incredibly special nature on Statia.”

Results

Using this method, researchers sampled 162 locations across St. Eustatius and estimated that Coralita was the dominant canopy cover (>50%) on over 3% of the island (64 ha). Perhaps more importantly, this map also showed that Coralita was not randomly distributed but generally found, for example, in areas of water accumulation, near roads or near drainage channels. Furthermore, Coralita was often found in grasslands and areas of development and is relatively rare in natural forests, highlighting how human disturbances can promote the spread of Coralita. It is important to note that data filtering and physical limitations of using satellite imagery means that Coralita growing under trees or shrubs or in smaller patches is likely underrepresented in this study.

Map of the distribution of Coralita on St. Eustatius (Haber et al., 2021)

 

Conservation Implications

Even with the physical limitations, the fact that this study is cost effective and repeatable means that consistent comparisons of Coralita’s distribution can be made over time. These comparisons are vital in understanding how populations and habitats are shifting, granting conservationists a fantastic tool in forecasting the spread of invasive species. Arguably the greatest asset of the Caribbean is its vast biodiversity. Already threats of climate change, habitat loss, invasive species and urban development are upsetting this fragile balance. St. Eustatius, although small, is home to several endemic plant species, two of which are the Statia morning glory and Statia milkweed, along with the critically endangered Lesser Antillean Iguana which could all be threatened by the habitat alterations of Coralita growth.

To read more, please find the full report on the Dutch Caribbean Biodiversity Database using the link below.

https://www.dcbd.nl/document/high-spatial-resolution-mapping-identifies-...

 

Article published in BioNews 48

 

Date
2021
Data type
Media
Theme
Education and outreach
Research and monitoring
Geographic location
St. Eustatius
Author

Two new nonnative reptiles identified on Saba

Wageningen University and Research and the University of Applied Sciences Van Hall Larenstein researchers have recently identified two new nonnative reptiles on Saba. The smooth-scaled tegulet and Brahminy blindsnake are both able to reproduce asexually, so their populations could expand quickly. Understanding the impact of their introduction will be key in protecting the biodiversity of Saba.

The island of Saba is home to five native species of reptiles, one snake (red-bellied racer) and four lizards (Saban anole, Saban black iguana, Saban least gecko, and the turnip-tailed gecko). Recently, two additional non-native species were identified, the smooth-scaled tegulet (Gymnophthalmus underwoodi) and Brahminy blindsnake (Indotyphlops braminus).  Exactly how these two species arrived on Saba is still unknown, however its likely they hitched a ride over from St. Maarten, since almost everything that arrives on Saba must go through St. Maarten first.

Smooth-Scaled Tegulet 

Photo credit: Thijs van den Burg

The smooth-scaled tegulet (Gymnophthalmus underwoodi) has been identified across the island and was first spotted in May 2020. Researchers from Wageningen University and Research and the University of Applied Sciences Van Hall Larenstein were able to capture five individuals from a variety of different life stages. These lizards have been observed on over 50% of the island, in habits which vary between gardens, dry forest and rocky slopes.  The wide spread dispersal of this species suggests it’s been on the island for a while.  These populations are expected to continue to increase as these lizards are very quick to reproduce.

Brahminy Blindsnake

More recently, a local resident has encountered at least two different Brahminy blindsnakes (Indotyphlops braminus) in her garden along the Windward side between May and July of 2021. Although no other observations have been made, this species is widely introduced on neighboring islands, so it’s presence on Saba is not surprising. Although there are currently no known documented native blindsnakes on Saba, it is possible for these species to go undetected, as was recently noticed on St. Eustatius with the discovery of the native blindsnake (geomotus) in 2020.

Island Impact

There had previously been two known nonnative amphibians and reptiles on Saba, so the addition of these two now doubles that list. Furthermore, currently 40% of all terrestrial reptiles and amphibians on Saba are nonnative species. Although direct competition between these two new species and native species is not expected, invasive species are considered among the top drivers of biodiversity loss and ecosystem change around the world. Understanding and addressing this issue will be key in preserving the unique biodiversity on Saba.

Report your sightings

If you happen to spot either one of these new reptiles while on Saba, you can report it on https://dutchcaribbean.observation.org. This is a free website and app which allows local citizens to report sightings of important plants and animals. These tools are available in over 40 languages and can be used by biologists and citizens and tourists alike. Species reports by local communities are invaluable for nature conservation efforts to help increase public awareness and overall species protection.

Read the full report entitled “Establishment of two nonnative parthenogenetic reptiles on Saba, Dutch  Caribbean: Gymnophthalmus underwoodi and Indotyphlops braminus” using the link below

 

https://www.dcbd.nl/document/establishment-two-nonnative-parthenogenetic...

 

Article published in BioNews 48

 

Date
2021
Data type
Media
Theme
Education and outreach
Research and monitoring
Geographic location
Saba
Author

Action required to curb Statia’s invasive green iguana threat

A new study by Wageningen Marine Research, St. Eustatius National Parks Foundation and Caribbean Netherlands Science Institute highlights the need for a continuation of the rapid response removal campaign to control the invasive green iguana population. Through displacement and hybridization, the green iguana threatens to wipe out the endemic Lesser Antillean Iguanas of St. Eustatius.  

The Lesser Antillean Iguana, , is an IUCN Red List Critically Endangered species, which has disappeared from most of its habitat, including St. Maarten. This species is endemic to St. Eustatius and is the largest native vertebrate on the island. Its main threat comes from displacement by and hybridization with the invasive species green iguana, Iguana iguana.  In fact, St. Eustatius is one of the last three major islands where this species was (until recently) still free from hybridization.  Biological invasions can create several issues which threaten biodiversity, the environment, agriculture, livelihoods, health, and local culture. 

Photo credit: Philippa King

Rapid Response 

In February of 2016, an adult female green iguana was caught in Princess Estates on St. Eustatius. Green iguanas and their hybrid offspring can be most easily distinguished from the native iguana based on their banded tail and the large scale on their cheek (see figure).  It was unknown how long this individual had been on the island and if she had already laid eggs, potentially introducing additional iguanas to the area. In response, the Ministry of Economic Affairs agreed to fund a limited Rapid Response Removal Campaign (RC) on the island.  

During the RC, three visual surveys were conducted throughout key risk areas.  In total, 409.5 hours were spent over 40 days, resulting in a single detection.  This low detection rate suggested that the RC occurred early in the invasion process and highlighted the need to stay vigilant. Luckily, local publicity via newspaper and radio programs led to a number of publicly reported sightings. Among these reports and opportunistic encounters by park management staff, an additional five green iguanas and their hybrids were captured before the campaign ended in January 2017, and an addition eight have been captures since. 

Research 

As part of the RC, a study was conducted by Wageningen Marine Research, St. Eustatius National Parks Foundation and Caribbean Netherlands Science Institute (CNSI) to learn more about this invasion. In addition to tracking population data during the surveys, they also worked to identify introduction events, points of entry and likely points of origin.  The harbor of St. Maarten was identified as the source of the most recent 2020 introductions, as this harbor serves as a major inter-island transshipment hub within the Lesser Antilles.  This recent study highlights four apparently distinct green iguana introduction events between 2013 and 2020, one of which was likely intentional and three of which were from incidental stowaways arriving on container ships. 

Photo credit: Dolfi Debrot

Moving Forward 

Luckily even four years after the RC the numbers of green iguanas and their hybrids appears to be limited.  This gives researchers hope that it is not too late to stop the invasion before it heavily interbreeds with and thus effectively wipes out the island’s critically endangered Lesser Antillean iguana.  Research alone will not be enough to control this issue. Investment both in finances and in capacity necessary to prevent introduction and spread of these iguanas will be required.  RCs are significantly lower in cost than full invasive species removal projects, so the early detection and active management provides a unique opportunity for the island to eradicate this threat while still possible and affordable.   

Report your sightings 

If you happen to spot a green iguana while on St. Eustatius, you can report it to the local park authority STENAPA (+599 318 2884) or CNSI (+599 318 2040) as well as on https://dutchcaribbean.observation.org. This is a free website and app which allows local citizens to report sightings of important plants and animals. These tools are available in over 40 languages and can be used by biologists and citizens and tourists alike. Species reports by local communities are invaluable for nature conservation efforts to help increase public awareness and overall species protection.  

 

Read the full report on the Case Study of a Rapid Response Removal Campaign for St. Eustatius on the Dutch Caribbean Biodiversity Database. 

https://www.dcbd.nl/document/st-eustatius-invasive-alien-green-iguana-ca...

 

Article published in BioNews 47

Date
2021
Data type
Media
Theme
Education and outreach
Research and monitoring
Geographic location
St. Eustatius
Author

New field guide on invasive seagrass flowers

Seagrasses are marine flowering plants that can reproduce both sexually (through flowering and subsequent seed formation) and asexually (through clonal growth). Sexual reproduction increases genetic diversity, resilience and dispersal success of seagrasses. A recent study discovered that the first report of sexual reproduction of a successful invasive seagrass was incorrect, and therefore released a new field guide to improve future determination.

Photo credit: Henkjan Kievit

The invasive seagrass Halophila stipulacea originating from the Red Sea and Western Indo-Pacific, has been successfully invading the Mediterranean Sea since 1894 and the Caribbean Sea since 2002. It was shown to outcompete native seagrass species and affect local ecosystem functioning.

In this new paper, WUR PhD candidate Fee Smulders found that so far, only male flowers have been described of the successful invasive seagrass species H. stipulacea in the Caribbean Sea. Female flowers and fruits have not been reported. This means that fragmentation and fast clonal growth may be the only factors explaining its current success, without genetic adaptation capacity. This needs to be taken into account in further studies studying H. stipulacea expansion.

In-depth monitoring of reproductive structures in invaded seagrass meadows, both in the Mediterranean and the Caribbean Sea is important to assess further invasion potential.

Because the fruits and flowers of  H. stipulacea have been misidentified in the past, we have developed a field guide with a dichotomous key, to take into the field and easily identify the various structures by eye. We call upon (citizen) scientists to keep an eye out underwater when they are in the Caribbean, to be able to predict future invasion success of this species.

– Fee Smulders

The field guide can be found in the supplementary material of the paper, and reports can be made in the online global database www.seagrassspotter.org.

Or check the field guide directly in the DCBD:

https://www.dcbd.nl/sites/default/files/documents/FIeldguide_Hstipulacea...

 

 

Article published in BioNews 44

 

Date
2021
Data type
Media
Theme
Education and outreach
Research and monitoring
Geographic location
Aruba
Bonaire
Curacao
Saba
Saba bank
St. Eustatius
St. Maarten
Author

Biosecurity concern for humanitarian aid highlighted by Caribbean organizations

Although the La Soufrière volcano on St. Vincent saw its latest explosive eruption over a week ago, and the threat level has decreased to Orange, caution is still necessary. Uncertainty for the St. Vincent population therefore remains, as thousands of people had to evacuate their villages and stay elsewhere on the island. Further uncertainty and hardship are caused by the eruptions’ effect on local food and water supplies. Gratefully, in a region where catastrophic weather events are not uncommon, regional organizations and nations quickly mobilized relief efforts to aid Vincentians.

In a letter to the journal Science, biologists from 12 Caribbean organizations, including STENAPA on St. Eustatius, highlight the need to prioritize both humanitarian aid and biosecurity when responding to natural disasters. The authors note how bypassing biosecurity could cause additional long-term harm to both the local ecosystems and the human population. Erik Boman, Director of STENAPA, pointed out that this threat is especially grave on islands. The letter also “urge governments and aiding parties responding to catastrophes to recognize and mitigate potential risks”.

Several of the authors have been involved in invasive species control on Dominica, where during the humanitarian aid campaign that followed the passing of Hurricane Maria in 2017, several non-native species were introduced. The local NGO WildDominique is currently working hard to remove both amphibian and reptile species that established populations there. The green iguana is also a biosecurity issue for local iguana, Iguana delicatissima on St. Eustatius. Although thousands of dollars have already been invested in these eradication efforts, a complete assessment of all species that arrived with the aid supplies still awaits. In the aftermath of natural disasters, when the natural environment is heavily affected and recovering, arriving non-native species will have the opportunity to spread out further and would form a major threat to the isolated and native flora and fauna on the island.

The letter further addresses the need for wide and multi-organizational collaborations to prepare for future large-scale humanitarian aid campaigns, of which each will be unique.

Link to Letter at Science: https://science.sciencemag.org/content/372/6542/581

 

Article published in BioNews 43

 

Date
2021
Data type
Media
Theme
Education and outreach
Research and monitoring
Geographic location
St. Eustatius

Case study of a Rapid Response Removal Campaign for the invasive alien green iguana, Iguana iguana

Abstract

The Invasive Alien Green Iguana (IAGI), Iguana iguana, has spread worldwide via the pet trade, as stowaways and via other means and has become a pest species of global concern. It also represents a major threat to the endemic Lesser Antillean Iguana, Iguana delicatissima, on St. Eustatius. Following the capture of an adult female IAGI on St. Eustatius in early 2016, we conducted a Rapid Response Removal Campaign (RC) from April 2016 to January 2017. Three sets of directed visual surveys totaling 409.5 observer hours and covering a combined trajectory of 114.2 km realized only a single detection of a hybrid that was later removed. During the remainder of the campaign period, an additional four IAGI hybrids were opportunistically detected and removed thanks to park staff or community involvement. Since the end of the campaign, eight additional detections and removals have been realized, three of which were IAGIs caught while offloading freight in the harbour and five of which were hybrids caught in surrounding suburban areas. We suggest that at least four distinct IAGI introductions to St. Eustatius occurred between 2013 and 2020. Our results show the value of motivating and mobilizing stakeholders and the public at an early stage of an invasion. Since the program’s initiation, eight of the 13 iguanas detected for culling were thanks to public and key stakeholder support and involvement. Four years after our campaign, the number of IAGIs and their hybrids still appear to be limited and concentrated in and around inhabited areas. Additional removal campaigns should be initiated as soon as possible, firmly based in public outreach, motivation and engagement. New legislation is needed to prohibit the importation, possession and harbouring of IAGIs or hybrids and to provide a framework for long-term structural funding required for effective control and removal. Routine fumigation and rigorous inspection of arriving cargo to eliminate the risk of stowaway IAGIs are also recommended. Culling of IAGIs is recommended for the port of St. Maarten, which serves as a major point of dispersal of IAGIs to St. Eustatius and likely also other islands in the region.

Date
2022
Data type
Scientific article
Geographic location
St. Eustatius

Mapping the economic loss of ecosystem services caused by the invasive plant species Antigonon leptopus on the Dutch Caribbean Island of St. Eustatius

Abstract
Invasive species are a worldwide threat to biodiversity, especially on Caribbean islands.
Through their impact on the structure and functioning of ecosystems, they also affect
ecosystem services. Therefore, invasive species can have profound socio-economic
effects. On the Dutch Caribbean Island of St. Eustatius, the invasive perennial vine Coralita
is present on roughly 33% of the Island. While ecological damage is evident, effective
management strategies are still lacking. This study links the ecological, cultural and
societal effects of the invasion to the economy of the Island by estimating the ecosystem
service losses due to Coralita in monetary value. We have spatially assessed the
economic value of five main ecosystem services (tourism, non-use value, carbon
sequestration, archaeology and local cultural and recreational value) to the different
habitats on the Island and estimated the loss of these values under three scenarios of
Coralita cover: 0%, 3% and 36% dominant cover. The baseline scenario of 0%
demonstrated a total ecosystem service value of $2.7 million per year, concentrated on the Quill volcano. The 3% and 36% scenario showed a yearly loss of $39,804 and $576,704, respectively, with the largest losses located on the northern and eastern slopes of the Quill.
These areas should be prioritised for management and the known potential gain per area
enables choice of strategy, based on cost-benefit considerations. To reduce further
economic loss by Coralita, we urgently advise an immediate management strategy and
ongoing research into eradication and restoration methods.

Keywords
BES Islands, Coralita, economic value, invasive species, spatial assessment, scenario
mapping

Date
2021
Data type
Scientific article
Theme
Education and outreach
Research and monitoring
Journal
Geographic location
St. Eustatius

Comparing the dietary niche overlap and ecomorphological differences between invasive Hemidactylus mabouia geckos and a native gecko competitor

Abstract

Hemidactylus mabouia is one of the most successful, widespread invasive reptile species and has become ubiquitous across tropical urban settings in the Western Hemisphere. Its ability to thrive in close proximity to humans has been linked to the rapid disap-pearance of native geckos. However, aspects of Hemidactylus mabouia natural history and ecomorphology, often assumed to be linked with this effect on native popula-tions, remain understudied or untested. Here, we combine data from ∂15N and ∂13C stable isotopes, stomach contents, and morphometric analyses of traits associated with feeding and locomotion to test alternate hypotheses of displacement between H. mabouia and a native gecko, Phyllodactylus martini, on the island of Curaçao. We demonstrate substantial overlap of invertebrate prey resources between the species, with H. mabouia stomachs containing larger arthropod prey as well as vertebrate prey. We additionally show that H. mabouia possesses several morphological advantages, including larger sizes in feeding-associated traits and limb proportions that could offer a propulsive locomotor advantage on vertical surfaces. Together, these findings pro-vide the first support for the hypotheses that invasive H. mabouia and native P. martinioverlap in prey resources and that H. mabouia possess ecomorphological advantages over P. martini. This work provides critical context for follow-up studies of H. mabouiaand P. martini natural history and direct behavioral experiments that may ultimately il-luminate the mechanisms underlying displacement on this island and act as a potential model for other systems with Hemidactylus mabouia invasions.

KEYWORDSfood web, invasive species, trophic ecology, urbanization, vertebrate biodiversity loss
 

Date
2021
Data type
Scientific article
Theme
Education and outreach
Geographic location
Curacao