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Two new papers out!—four new skink species described, and a research paperPosted on 10 March, 2011It´s been a rewarding couple of months for me with two papers finally out! The first paper I mentioned is Chapple et al 2011, and describes four new species of skink (Oligosoma tekakahu, O. repens, O. toka and O. burganae) along with re-describing the cryptic skink O. inconspicuum. What was extremely surprising in our research was that three species (repens, toka and burganae) were virtually indistinguishable (cryptic) from O. inconspicuum and were only largely identified using DNA techniques, while two ´forms´, included the very highly distinctive-looking ´mahogany skink´, turned out to be of the same species as O. inconspicuum, despite looking so different (´anti-cryptic´). Phylogeography and taxonomic revision of the New Zealand cryptic skink (Oligosoma inconspicuum; Reptilia: Scincidae) species complex. DAVID G. CHAPPLE, TRENT P. BELL, STEPHANIE N.J. CHAPPLE, KIMBERLY A. MILLER, CHARLES H. DAUGHERTY & GEOFF B. PATTERSON. Zootaxa 2782: 1–33 (3 Mar. 2011) 10 plates; 70 references The New Zealand skink fauna is highly diverse and contains numerous cryptic, undescribed or hitherto undiscovered species.We completed a taxonomic revision of the cryptic skink (Oligosoma inconspicuum) species complex using molecular (550 bp of the ND2 mitochondrial gene) and morphological analyses. Four new species are described, with each diagnosable by a range of morphological characters and genetic differentiation from several closely related species: O. inconspicuum (sensu stricto), O. notosaurus, O. maccanni, O. stenotis and O. grande. Oligosoma tekakahu sp. nov. is restricted to Chalky Island in Fiordland, and is most closely related to O. inconspicuum. and O. notosaurus. The other three new species are restricted to particular mountainous regions in central and western Otago (O. burganae sp. nov., Lammermoor and Rock and Pillar Ranges; O. toka sp. nov., Nevis Valley; O. repens sp. nov., Eyre Mountains) and are most closely related to O. stenotis and O. grande. We also re-described O. inconspicuum. Two proposed new taxa, the ´Big Bay´ skink and ´mahogany´ skink, were found to represent Westland/Fiordland populations of O. inconspicuum rather than distinct taxa. We discuss the evolutionary and phylogeographic implications of cryptic and ´anti-cryptic´ species within the O. inconspicuum species complex, and suggest that morphologically aberrant populations are the result of local adaptation to novel selective regimes. Click here for the link to the paper and scroll down to the reference (journal subscription or article purchase required). You can also ask me for a copy. The other paper I mention is the outcome of a study looking at the effects of toe-clipping on a population of skinks in Alexandra (Central Otago). Relative effects of toe-clipping and pen-marking on short-term recapture probability of McCann´s skinks (Oligosoma maccanni). CHRISTOPHER JONES & TRENT BELL. HERPETOLOGICAL JOURNAL 20: 237–241, 2010 There has been much debate about the use and acceptability of toe-clipping as a means of permanently marking reptiles and amphibians during scientific surveys. Trapping studies of reptiles and amphibians are frequently, although not always, compromised by low probabilities of recapture of individuals following their initial capture and marking. Low recapture rates can influence the precision of estimates of population size and home range that are derived from trapping data. We investigated whether there was a difference in the short-term probability of recapture of toe-clipped McCann´s skinks (Oligosoma maccanni) compared with those marked non-invasively with a pen. We pitfall-trapped skinks for seven days in a dry scrub habitat on the South Island of New Zealand. On first capture, skinks were individually marked by either toe-clipping or writing a code on their ventral surface with a silver marker pen. The resulting recapture histories for 118 skinks were analysed using Huggins´ closed population models in the MARK program. The best supported models indicated that recapture probability was significantly affected by sex (females > males) and previous toe-clipping experience (previously clipped > not). There was no support for an effect of marking method on short-term recapture probability, which is likely to be affected by other sampling factors such as trap spacing, social behaviour or response to handling. Females´ higher recapture probability may reflect their increased energetic requirements during the breeding season, making them more likely to enter traps in search of food. We speculate that previous experience of toe-clipping is a surrogate for age and social dominance leading to increased access to traps. For a copy of the paper, here is the link. Again, journal subscription or article purchase required. Or ask me for a copy. It is always a great feeling to achieve notable milestones in getting your work published and out there. Please enjoy. cheers, t 241 years of work on lizards in NZ online now!—the NZ Lizards Database now releasedPosted on 11 November, 2010It is with epic excitement and palpable relief that we have now launched the NZ Lizards Database. Essentially this is 241 years of accumulated knowledge and references to anything and everything on NZ´s unique lizards (and one wee Australian skink), along with great photographs of most species. The first reference was published in 1769 in French, and even Captain Cook himself in 1777 contributed his own two cents worth towards our knowledge— "... for we found no reptile here, except two or three forts of fmall harmlefs lizards" CAPTAIN JAMES COOK, FEBRUARY 1777 Today, we now have over 100 recognised and putative species in New Zealand, all but one are endemic, and all but one of our endemic species give live birth, due to NZ´s cold climate, an almost unique adapation globally. In the database, there are also over 3,200 references and counting; and also around 300 data fields per 100 species (i.e. about 30,000 fields in total in the synopses)! The database has been developed to help researchers, students, conservation & biodiversity managers, and many more to more easily access the required knowledge for informed decision making and management. Here is the link: NZ Lizards Database The database will continue to grow and expand over time, due to the relentless progress being made in this field on several fronts, including taxonomy, conservation & biological research. Please do enjoy the resource, and please provide updates and feedback using the forms available on every page of the system, or please get in touch with me. cheers, Trent EcoGecko Herpetofauna Conservation & Research Award winners announced!Posted on 30 September 2010Today we announce the EcoGecko Herpetofauna Conservation and Research Award winners. Congratulations to Michel Ohmer of the University of Otago, and also to the Bream Head Conservation Trust in Northland. Both winners will receive $1,000 each towards their research and conservation projects. To read about their projects, please go to here. Trent & Sarah EcoGecko Consultants Inaugural Winners (2010) Individual/Student winner: Michel Ohmer. Project Title: The relationship between infectiousness and susceptibility: Chytridiomycosis disease dynamics in New Zealand's frog fauna.  Project Summary: The spread of chytridiomycosis, an emerging infectious disease caused by the fungal pathogen Batrachochytrium dendrobatidis (Bd), has been associated with the decline or extinction of over 200 amphibian species globally. This disease became a key-threatening process to our unique native frog fauna, Leiopelma spp., after its first discovery in New Zealand in a population of introduced frogs in 1999. In order to evaluate this threat, we tested the susceptibility of two of New Zealand's native frog species, Leiopelma pakeka and Le. hochstetteri, to Bd infection and found that both species demonstrate low susceptibility in the laboratory. In our susceptibility trials, no native frogs exhibited clinical signs of disease, which was consistent with low infection levels as determined by quantitative PCR, and all individuals cleared infection by 15 weeks post exposure. In contrast, the introduced tree frog, Litoria ewingii, is highly susceptible to chytridiomycosis, and exhibits 100% mortality in the laboratory. These results give us the opportunity to investigate another aspect of this disease that has yet to be quantified in any study: infectiousness, or the capacity of an infected host to transmit infection following contact with a susceptible host. A major gap in our current understanding of chytridiomycosis involves the rate of zoospore production and release from an infected host, and how this in turn relates to a frog's susceptibility level. Thus, we propose to investigate infectiousness in species of both native and introduced frogs, thereby determining their transmission function. This will allow us to infer the life history of the pathogen on the frog, which will be influential in creating predictive models for disease modeling within and across populations. Using this information, we can quantify the transmission probability for the species under question, allowing for the modeling of multi-species system dynamics. Community Organisation winner: Bream Head Conservation Trust. Project Title: Responses of arboreal gecko fauna to intensive predator control at the Bream Head Scenic Reserve. Project Summary: Geckos are disappearing from unmanaged mainland forest throughout New Zealand due to introduced predators. This is particularly true in Northern New Zealand where the climatic conditions support high densities of introduced predators year round. Although many gecko species have insurance populations on offshore islands, there are some species that are only found on the mainland (Naultinus grayi and Naultinus 'Northcape' for example) or that have only one island safe haven (Naultinus elegans for example). Although conservation managers assume that routine predator control assists gecko (and other lizard) fauna, it is unclear at what 'level' of control gecko populations respond, if they do at all. Determining if and how geckos respond to predator control is crucial to successfully managing their populations on the mainland, and is an essential step to saving mainland endemic species. This study seeks to determine if arboreal geckos present in Bream Head Scenic reserve (Hoplodactylus pacificus, Naultinus elegans, Hoplodactylus granulatus) respond to intensive predator control, using closed-cell foam covers and visual spotlighting methods. New paper out!—Assisted reproduction of lizardsPosted on 13 September 2010I recently assisted Frank Molinia in developing new techniques relating to artificial insemination of skinks as a genetic management tool. While our work is ongoing with a focus on the nationally endangered grand and Otago skinks this upcoming summer, our pilot study is now published. We made promising inroads with regards to semen extraction from males and insemination of females, but we were unable to prove the technique in the end (i.e. pregnancy) because of a mite infestation of the captive population causing deaths of the inseminated females. This year, however, we will now take this research to the next level by working directly with grand and Otago skinks. Download the paper here. ASSISTED BREEDING OF SKINKS - OR HOW TO TEACH A LIZARD OLD TRICKS! FRANK C. MOLINIA, TRENT BELL, GRANT NORBURY, ALISON CREE; AND DIANNE M. GLEESON. Herpetological Conservation and Biology 5(2):311-319. Reproductive technologies are invaluable tools for understanding how different species reproduce. Contemporary techniques like artificial insemination established long ago in livestock have been used to assist the breeding of threatened species ex situ, even restoring them to nature. Key to successfully adapting these technologies, often to few numbers of endangered animals, is initial testing and development of procedures in a taxonomically related model species. McCann´s Skink (Oligosoma maccanni) is a viviparous lizard that is still relatively abundant and its reproductive cycle in the subalpine area of Macraes Flat in southern New Zealand has recently been described. Assisted breeding techniques are being developed in this skink as a model for threatened lizard species, such as the Grand Skink (Oligosoma grande) and Otago Skink (Oligosoma otagense). Progress on methods to collect, assess and store sperm, and artificial insemination are reported here. These techniques will need refinement to be effectively adapted to threatened lizards but will significantly increase our knowledge of their unique reproductive mechanisms. In the longer term they are expected to improve substantially captive breeding success and will be vital tools to aid genetic management of animals bred for release to restored ecosystems and secure genetic repositories for future restoration needs. On Waiheke TimePosted on 2 July 2010As part of our collaborative work with the Auckland Regional Council and Bioresearches Group, we spent time on Waiheke Island in one of the wildlife sanctuaries setting up a long-term gecko monitoring programme. Thanks to Andy and Alice, the Butler family, the Izzard family, Lavender Blue and GreenAcres for their involvement. We are particularly chuffed about this work, since long-term research (possibly 15 or more years in this case) is a fairly rare thing, as science tends to run on a 3-5 year grant cycle. So, off to Waiheke Island we went with a truck full of closed-cell foam covers. Here is one of the wonderful things we encountered while on the island: Whakanewha Regional Park. The park was established in 1994 and it has come a long way since. What struck us about the Park is the sense of ownership and involvement that we encountered from the Waiheke community. From what we could tell, the park is kept going by ongoing collaboration between the Auckland Council staff and local volunteers, and what a lot they have achieved! Within sixteen years, the Park has been restored, become an open predator-trapped sanctuary, and areas of the shore used for breeding habitat by the threatened, and endemic, New Zealand dotterel (Charadrius obscurus) have been fenced off to keep those bipedal mammalian pests out. In fact, the Whakanewha dotterel breeding programme has become one of the most successful in New Zealand! 
Whakanewha Regional Park Searches about the place revealed a surprising number of active forest geckos deep in the jungle, given that it was the middle of winter. We were even further amazed by the locals´ stories of geckos in their backyard—it seems most of the people there have a few geckos running around their houses and yards. Andy, one of the Park Rangers, has a forest gecko that has taken up residence in one of the ceiling cross-beams in his house! Presumably it lives on flies and other insects that are attracted into the house. We ended up putting up 400 closed cell-foam covers up on tree trunks, with 200 in predator-trapped, and 200 in non-predator-trapped forested areas. Over time, this will hopefully allow us to determine the effect that predator control is having on the resident forest-dwelling geckos. We anticipate that the covers will be checked for gecko presence by park staff and volunteers next summer, and then every three years for the next fifteen years. We are very much looking forward to see what kind of trends we will see in this gecko population, as well as in another three sites selected in the Auckland region for this monitoring programme, which we will write about soon! Retrospectives—Alpine lizard research in FiordlandPosted on 23 April 2010You really should check out James Reardon´s blog at http://jamesreardon.wordpress.com/. James recently visited the Sinbad Gully in Milford Sound, New Zealand and his photographs brought back lots of memories of field work in the Fiordland National Park for new species of lizards. I recently described the Sinbad skink (Oligosoma pikitanga) with Geoff Patterson, and so I trawled through my field photographs of lizards and their extreme habitat. As a consequence, here we will see this skink, the ´mahogany´ form of the cryptic skink (Oligosoma inconspicuum), cascade gecko (Hoplodactylus (=Mokopirirakau) sp. ´Cascade´), and the Barrier skink (Oligosoma judgei) from the adjacent Darran Mountains—which we also described, then finally we will visit the Te Kakahu skink (Oligosoma sp. ´Te Kakahu´). I´ll start off with the Sinbad here. Enjoy!  Mitre Peak towering over Milford Sound. Mitre is the gateway to the Sinbad, valley of diamonds.  The Sinbad, where three species of lizards were recently discovered.  Sinbad skink.  Cascade gecko.  This is the 'mahogany' form of the cryptic skink. Now I will take you to the Darran Mountains, where the Barrier skink (Oligosoma judgei) was rediscovered again after 39 years of obscurity by Murray & Bronwyn Judge. The Cascades gecko has also been found here.  Darran Mountains, where the Barrier skink and Cascades gecko are known.  Barrier skink You´ll be interested to hear that the genetic divergence between the Sinbad skink and the Barrier skink was only 3%, which is indication of the recent geological and climatic upheaval of the area. Fiordland was, in fact, once a series of glaciers with interspesed nunataks. Did each species of lizard survive and evolve on separate mountaintops?  Bronwyn & Murray Judge, whom rediscovered the Barrier skink. Let´s hop and skip over to Chalky Island, where another new species was recently discovered. This skink is in the process of being described. Chalky is a very remote island in the far south of the Fiordland National Park.  Chalky Island, also known as Te Kakahu, is the home of Te Kakahu skink.  Te Kakahu skink. Now finally, I would like you to gaze on this photograph and wonder... what else remains to be discovered in the Fiordland National Park´s mountains? I´ll keep you posted.  Unexplored mountain, Fiordland National Park. Chevies, chevies and more chevies!Posted on 19 April 2010Sarah and myself recently spent time in April 2010 surveying Windy Hill Pest Management Area on Great Barrier Island for chevron skinks (Oligosoma homalonotum) and Hochstetter´s frog (Leiopelma hochstetteri). Although no frogs were found on this particular trip, our team captured or trapped five chevron skinks, which are one of the most elusive lizards in New Zealand. Our current research involves surveys for the above species and also the elusive striped skink (Oligosoma striatum), and our objective also included training the local field team at Windy Hill on herp skills, and developing management plans for the lizards at Windy Hill. On this trip, we found Pacific geckos (Hoplodactylus pacificus, now known as Dactylocnemis pacificus), forest geckos (Hoplodactylus granulatus, now known as Mokopirirakau granulatus), ornate skinks (Oligosoma ornatum) and copper skinks (Oligosoma aeneum). We will soon return for the second expedition in May 2010, trialling a new trap for striped skinks and surveying for frogs again. Thanks to Judy, Kevin, Dean, Rachel, Mallory, Mick, James, Halema and our newly anointed Chevie King, Dylan for a great & memorable first expedition. Here are the photographs. 
Windy Hill Pest Management Area, Great Barrier Island. 
The chevie team. Photo: Dylan Van Winkel. 
Chevron skink country. Photo: Dylan Van Winkel. 
Pacific gecko. 
Forest gecko. 
Ornate skink. 
Chevron skink. 
Individual diagnostic markings of head in chevron skink. 
Individual diagnostic markings of chin in chevron skink. |