Over-ocean dispersal inferred from the saltwater tolerance of lizards from Taiwan

Abstract BackgroundFor non-marine organisms, crossing the sea requires the challenges of dehydration and hypersalinity to be faced. Thus, the rate of water loss and saltwater tolerance determine the ability of species to disperse over sea and further influence species distribution. However, this association between physiology and ecology has rarely been investigated in terrestrial vertebrates. In this study, we examined the lizard species differently distributed across Taiwan and the adjacent islands to determine whether these physiological responses reflect the geographical distribution. We performed immersion experiments on individuals and eggs to test the rate of water loss and the saltwater tolerance in the six chosen species, that is, four native species (Plestiodon elegans, Eutropis longicaudata, Diploderma swinhonis, and Hemidactylus frenatus) and two introduced species (E. multifasciata and Anolis sagrei). Results For the individuals, the results showed that P. elegans had the highest rate of water loss and the lowest saltwater tolerance, whereas E. longicaudata and E. multifasciata showed the lowest rate of water loss and the highest saltwater tolerance. D. swinhonis, H. frenatus, and A. sagrei had medium measurements compared with the aforementioned species. On the other hand, for the eggs, only the rigid-shelled eggs of H. frenatus were not influenced by the water immersion and were incubated successfully after experimental treatment. In contrast, the parchment-shelled eggs of E. longicaudata and D. swinhonis lost or gained water dramatically in the experiments, and none of them hatched after immersion. ConclusionsThese interspecies differences in water loss and saltwater tolerance strongly suggest the heterogeneity of over-ocean dispersal ability among these lizards. Combined with the historical geology and the origin areas of each species, the inferences of the results largely explain the current distribution of these lizards across Taiwan and the adjacent islands. Furthermore, this study also helps to elucidate the potential dispersal of two invasive species, E. multifasciata and A. sagrei, for conservation purposes.

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Trans-marine dispersal inferred from the saltwater tolerance of lizards from Taiwan

PLoS ONE ◽

10.1371/journal.pone.0247009 ◽

2021 ◽

Vol 16 (2) ◽

pp. e0247009

Author(s):

Min-Hao Hsu ◽

Jhan-Wei Lin ◽

Chen-Pan Liao ◽

Jung-Ya Hsu ◽

Wen-San Huang

Keyword(s):

Species Distribution ◽

Current Distribution ◽

Water Loss ◽

Physiological Responses ◽

Lizard Species ◽

Terrestrial Vertebrates ◽

Marine Dispersal ◽

Historical Geology ◽

Saltwater Tolerance ◽

Hemidactylus Frenatus

Dehydration and hypersalinity challenge non-marine organisms crossing the ocean. The rate of water loss and saltwater tolerance thus determine the ability to disperse over sea and further influence species distribution. Surprisingly, this association between physiology and ecology is rarely investigated in terrestrial vertebrates. Here we conducted immersion experiments to individuals and eggs of six lizard species differently distributed across Taiwan and the adjacent islands to understand if the physiological responses reflect the geographical distribution. We found that Plestiodon elegans had the highest rate of water loss and the lowest saltwater tolerance, whereas Eutropis longicaudata and E. multifasciata showed the lowest rate of water loss and the highest saltwater tolerance. Diploderma swinhonis, Hemidactylus frenatus, and Anolis sagrei had medium measurements. For the eggs, only the rigid-shelled eggs of H. frenatus were incubated successfully after treatments. While, the parchment-shelled eggs of E. longicaudata and D. swinhonis lost or gained water dramatically in the immersions without any successful incubation. Combined with the historical geology of the islands and the origin areas of each species, the inferences of the results largely explain the current distribution of these lizards across Taiwan and the adjacent islands, pioneerly showing the association between physiological capability and species distribution.

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Transepidermal Water Loss after Water Immersion

Siriraj Medical Journal ◽

10.33192/smj.2021.51 ◽

2021 ◽

Vol 73 (6) ◽

pp. 386-390

Author(s):

Rattanavalai Nitiyarom ◽

Nampen Siriwat ◽

Wanee Wisuthsarewong

Keyword(s):

Healthy Volunteers ◽

Water Loss ◽

Water Immersion ◽

Transepidermal Water Loss ◽

Total Water ◽

Previous Period ◽

Cumulative Percentage ◽

Significant Difference ◽

Males And Females

Objective: To observe changes in transepidermal water loss (TEWL) at different times after water immersion.Materials and Methods: TEWL values were measured before water immersion and at 3, 5, 10, 15, 20, and 30 minutes after immersion of the skin in water for 5 minutes.Results: Forty-one healthy volunteers were enrolled with an average age of 30.4±5.5 years. Twenty-five subjects were female and sixteen were male. The TEWL value before water immersion (TEWLbaseline) was 13.16±7.27 g/m2/h and TEWL values at 3, 5, 10, 15, 20 and 30 minutes after immersion were 23.21±7.67, 16.12±3.42, 14.76±6.36, 14.45±6.67, 13.53±4.67 and 12.96±5.18 g/m2/h, respectively. After immersion, TEWL values at 3 and 5 minutes statistically increased compared to TEWLbaseline (p<0.001). TEWL values between 10 to 30 minutes gradually dropped with no statistically significant difference compared to the previous period and TEWLbaseline. Although total water loss from the skin occurred within 30 minutes, 56.9% of it occurred within 10 minutes after immersion. There was no significant difference between TEWLbaseline in males and females but the TEWL values at 3, 5 and 15 minutes after immersion in males was higher than in females (p<0.05). Conclusion: TEWL statistically increased after water immersion for only 5 minutes. The cumulative percentage of TEWL was high within 10 minutes. Gender did not affect TEWL values before immersion; however, males experienced more water loss from the skin than females after immersion. Therefore, moisturizer should be applied immediately before TEWL occurs.

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Somewhat saved: a captive breeding programme for two endemic Christmas Island lizard species, now extinct in the wild

Oryx ◽

10.1017/s0030605316001071 ◽

2016 ◽

Vol 52 (1) ◽

pp. 171-174 ◽

Cited By ~ 8

Author(s):

Paul Andrew ◽

Hal Cogger ◽

Don Driscoll ◽

Samantha Flakus ◽

Peter Harlow ◽

...

Keyword(s):

Native Species ◽

Captive Breeding ◽

Biodiversity Loss ◽

Breeding Programme ◽

Lizard Species ◽

Christmas Island ◽

Captive Populations ◽

Captive Breeding Programme ◽

In Captivity ◽

In The Wild

AbstractAs with many islands, Christmas Island in the Indian Ocean has suffered severe biodiversity loss. Its terrestrial lizard fauna comprised five native species, of which four were endemic. These were abundant until at least the late 1970s, but four species declined rapidly thereafter and were last reported in the wild between 2009 and 2013. In response to the decline, a captive breeding programme was established in August 2009. This attempt came too late for the Christmas Island forest skink Emoia nativitatis, whose last known individual died in captivity in 2014, and for the non-endemic coastal skink Emoia atrocostata. However, two captive populations are now established for Lister's gecko Lepidodactylus listeri and the blue-tailed skink Cryptoblepharus egeriae. The conservation future for these two species is challenging: reintroduction will not be possible until the main threats are identified and controlled.

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Non-native small terrestrial vertebrates in the Galapagos

10.7287/peerj.preprints.26563 ◽

2018 ◽

Author(s):

Diego F Cisneros-Heredia

Keyword(s):

Native Species ◽

Galapagos Islands ◽

Current Status ◽

Ecosystem Functions ◽

Human Populations ◽

Tree Frog ◽

Galápagos Islands ◽

Species Introduction ◽

Terrestrial Vertebrates ◽

History Of

Humans have translocated thousands of species of flora, fauna and microorganisms to places they would never have reached on their own. Non-native species may have effects on biological communities, ecosystem functions and human populations. In island environments, the effects of spreading non-native species on native biodiversity can be severe and lead to native ecosystem transformation and even endemic species extinction. The Galapagos Islands are a region of particular interest and relevance to the issue of species introduction and invasiveness. In this paper, I analyse the current status of 25 non-native amphibians, reptiles and birds that have been reported in the Galapagos Islands. Six species have established self-sufficiently in Galapagos and may become invasive: Fowler’s snouted tree frog Scinax quinquefasciatus, common house gecko Hemidactylus frenatus, mourning gecko Lepidodactylus lugubris, dwarf gecko Gonatodes caudiscutatus, Peters’ leaf-toed gecko Phyllodactylus reissii, and smooth-billed ani Crotophaga ani. Domestic fowl Gallus gallus holds feral populations, which may have self-sufficient populations, but evidence is unclear. I provide information on the distribution and natural history of non-native species of amphibians, reptiles and birds in Galapagos, including new data about the introduction history of S. quinquefasciatus; evidence on the establishment of H. frenatus on Isabela and San Cristobal islands; the first published record of a non-native snake in Galapagos, Lampropeltis micropholis; the first evidence of predation on squamate reptiles by G. gallus in Galapagos; and evidence of a probable major impact by C. ani due to extensive predation on the endemic Galapagos carpenter bee Xylocopa darwini. I comment on the invasiveness and impact potential of non-native species in Galapagos, identify vulnerable islands for the arrival of non-native species, identify potential hitchhiker that could arrive in the future and propose that it is important to rethink about how we understand, manage and prevent introductions of non-native species. The new wave of introduced species in Galapagos is formed by small hitchhikers, species that are easily overlooked, may travel in high numbers and are highly linked to human-made environments.

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Lizards (Reptilia: Squamata) of the Corn Islands, Caribbean Nicaragua

Check List ◽

10.15560/9.6.1383 ◽

2013 ◽

Vol 9 (6) ◽

pp. 1383 ◽

Cited By ~ 1

Author(s):

Javier Sunyer ◽

Kirsten Elizabeth Nicholson ◽

John Gerhardt Phillips ◽

Jenny Ann Gubler ◽

Lenin Alexander Obando

Keyword(s):

Protected Areas ◽

Human Population ◽

Habitat Alteration ◽

Lizard Species ◽

Iguana Iguana ◽

Caribbean Islands ◽

Lepidodactylus Lugubris ◽

Ctenosaura Similis ◽

Hemidactylus Frenatus

The Corn Islands are two small Caribbean islands with the richest collection of endemic herpetofaunal taxa in Nicaragua. Despite increasing human population and associated habitat alteration, both islands lack protected areas. The lizard fauna of Great Corn Island consists of 14 species corresponding to nine families, and includes three endemic taxa. We collected three lizard species (Corytophanes cristatus, Gonatodes albogularis, and Hemidactylus frenatus) that were not previously recorded from that island. On Little Corn Island, where there were no previous records of lizards, we found seven species (Ctenosaura similis, Gonatodes albogularis, Hemidactylus frenatus, Holcosus undulatus, Iguana iguana, Lepidodactylus lugubris, and Norops unilobatus), all of which are also present on Great Corn Island.

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Genetic reconstruction of the invasion history of Anolis wattsi in Trinidad with a comment on the importance of ecological similarity to invasion success

Herpetological Journal ◽

10.33256/hj29.3.131137 ◽

2019 ◽

pp. 131-137

Author(s):

Keyword(s):

Native Species ◽

Geographic Origin ◽

Invasion Success ◽

Published Data ◽

Invasion History ◽

Lizard Species ◽

Anolis Lizard ◽

Scale Population ◽

History Of ◽

Multiple Species

Human activities have reshaped patterns of island biogeography for many groups of amphibians and reptiles. In Trinidad, an island in the West Indies with only one native Anolis lizard species, four additional anole species have been introduced since the 1800s. The most recent introduction, Anolis wattsi, native to Antigua, has become established despite the presence of multiple species of resident anoles. We used genetic data (mitochondrial DNA) to infer the geographic origin and genetic structure of introduced A. wattsi on Trinidad. We then gathered published data to compare eco-morphological traits of all anole species currently established on the island. We found three mtDNA haplotypes in Trinidad that clustered with two different clades from the northern part of the native range in Antigua, rejecting the hypothesis that the lizards originated in the pineapple-growing region of the south. However, a lack of fine-scale population structure precluded precise identification of the origin in Antigua of haplotypes introduced to Trinidad. Compared to the other anole species on Trinidad, A. wattsi is smaller, perches lower, and has a higher field body temperature. Thus, the successful establishment and spread of A. wattsi should not be surprising given the success of two previous introductions of anole species that were more similar ecomorphologically to the native species and each other, and the fact that Trinidad has relatively few anole species for its size.

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Cost-effective surveillance of an invasive species: application of info-gap theory to the Asian House Gecko Hemidactylus frenatus

10.21203/rs.3.rs-794258/v1 ◽

2021 ◽

Author(s):

Yang Liu ◽

Penghao Wang ◽

Melissa L. Thomas ◽

Dan Zheng ◽

Simon J. McKirdy

Keyword(s):

Invasive Species ◽

Native Species ◽

Cost Effective ◽

Expert Assessment ◽

Parameter Estimates ◽

Surveillance Systems ◽

Effective Manner ◽

Novel Method ◽

Hemidactylus Frenatus ◽

Population Threshold

Abstract Invasive species can lead to community-level damage to the invaded ecosystem and extinction of native species. Most surveillance systems for the detection of invasive species are developed based on expert assessment, inherently coming with a level of uncertainty. In this research, info-gap decision theory (IGDT) is applied to model and manage such uncertainty; surveillance of the Asian House Gecko, Hemidactylus frenatus Duméril and Bibron, 1836 on Barrow Island, is used as a case study. Our research provides a novel method for applying IGDT to determine the robust population threshold (K) to trigger detection, robust-optimizing surveillance costs rather than minimizing surveillance costs. We demonstrate that increasing the population threshold for detection increases both robustness to the errors in the model parameter estimates, and opportuneness to lower surveillance costs than the accepted maximum budget. This paper provides guidance for decision makers to balance robustness and required surveillance expenditure. IGDT offers a novel method to model and manage the uncertainty prevalent in biodiversity conservation practices and modelling. The method outlined here can be used to design robust surveillance systems for invasive species in a wider context, and to better tackle uncertainty in protection of biodiversity and native species in a cost-effective manner.

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Island biogeography of vertebrates in Georgian Bay Islands National Park

Canadian Journal of Zoology ◽

10.1139/z87-460 ◽

1987 ◽

Vol 65 (12) ◽

pp. 3041-3043 ◽

Cited By ~ 12

Author(s):

Fiona K. A. Schmiegelow ◽

Thomas D. Nudds

Keyword(s):

Island Biogeography ◽

National Park ◽

Nature Reserves ◽

Dispersal Ability ◽

Georgian Bay ◽

Terrestrial Vertebrates ◽

Number Of Species ◽

Theory Of Island Biogeography ◽

Dispersal Capability ◽

Bay Islands

Terrestrial vertebrates on 28 of 77 islands in Georgian Bay Islands National Park were examined by taxon (i.e., nonvolant mammals, herptiles, and birds) to determine whether the number of species on each island was affected by variation in dispersal capability and susceptibility to extinction, as predicted by the equilibrium theory of island biogeography. About 70% of the variation in number of species on islands was accounted for by the area of the islands. Species (S) – area (A) relationships (S = cAz) for birds, herptiles, and nonvolant mammals all differed significantly in slope and intercept (P < 0.05). Intertaxa comparisons revealed that birds exhibited the greatest numbers of species on all sizes of islands and smallest slope (z = 0.32); herptiles exhibited intermediate numbers of species on all sizes of islands and intermediate slope (z = 0.37). Of all taxa, nonvolant mammals exhibited the lowest numbers of species on all sizes of islands and greatest slope (z = 0.42), consistent with the predictions of the theory. These results reinforce earlier suggestions that designs for nature reserves should accommodate intertaxa variation in dispersal ability and susceptibility to extinction.

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An assessment of conflict areas between alien and native species richness of terrestrial vertebrates on a macro-ecological scale in a Mediterranean hotspot

Animal Conservation ◽

10.1111/acv.12330 ◽

2017 ◽

Vol 20 (5) ◽

pp. 433-443 ◽

Cited By ~ 5

Author(s):

A. J. Carpio ◽

J. A. Barasona ◽

J. Guerrero-Casado ◽

J. Oteros ◽

F. S. Tortosa ◽

...

Keyword(s):

Species Richness ◽

Native Species ◽

Terrestrial Vertebrates ◽

Ecological Scale ◽

Native Species Richness

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Purposes, outcomes and challenges of eradicating invasive mammals from New Zealand islands: an historical perspective

Wildlife Research ◽

10.1071/wr12064 ◽

2013 ◽

Vol 40 (2) ◽

pp. 94 ◽

Cited By ~ 37

Author(s):

D. R. Towns ◽

C. J. West ◽

K. G. Broome

Keyword(s):

New Zealand ◽

Native Species ◽

Historical Perspective ◽

Native Plants ◽

Deep Understanding ◽

Terrestrial Vertebrates ◽

Multi Scale ◽

Invasive Mammals ◽

Conservation Actions ◽

Future Work

Context Invasive mammals have been removed from at least 100 offshore islands around New Zealand, covering a total area of around 45 000 ha. Aims To review the outcomes of eradications, the statutory and social environment in which the eradications were conducted, and the lessons provided for future work. Methods Native species to benefit from the eradications were identified, as were the reasons for the eradications and the agencies responsible. Examples are provided using case studies. Key results Three loosely linked work streams were revealed: research into efficient baits and baiting methods, threatened species-led projects nested within priorities for species recovery and supported by legislation, and community-led projects instigated by restoration societies. At least 180 populations of 14 species of invasive mammals were removed. Numerous species of native plants, invertebrates and more than 70 species of terrestrial vertebrates are recovering or are likely to recover as a result of the eradications. Partnerships have been formed with Māori and innovative projects developed with community groups. Conclusions Eradications of invasive mammals are aggressive conservation actions that can have wide benefits for biodiversity but can also be controversial, technically demanding and expensive. Implications Eradications are multi-scale problems. If they are to gain public acceptance, evidence is needed in support. This evidence can include understanding the detrimental effects of invasive species, the likely responses of native biodiversity, and the benefits ensuing from their recovery. However, the way this evidence is gained and communicated will also require deep understanding of nuances in regional political and cultural environments.

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