Rare Species Conservatory Foundation

Loxahatchee, FL, United States

Rare Species Conservatory Foundation

Loxahatchee, FL, United States
Time filter
Source Type

Estes L.D.,Rare Species Conservatory Foundation | Estes L.D.,University of Virginia | Estes L.D.,Princeton University | Reillo P.R.,Rare Species Conservatory Foundation | And 3 more authors.
Remote Sensing of Environment | Year: 2010

Spatial distribution models are increasingly used in ecological studies, but are limited by the poor accuracy of remote sensing (RS) for mapping microhabitat (< 0.1 ha) features. Mapping accuracy can be improved by combining advanced RS image-processing techniques with microhabitat data expressed as a structural complexity index (SCI). To test this idea, we used principal components analysis (PCA) and an additive SCI method developed for forest ecology (calculated by re-scaling and summing representative structural variables) to summarize 13 microhabitat-scale (0.04 ha) vegetation structure attributes describing the rare mountain bongo antelope's (Tragelaphus eurycerus isaaci) habitat in Kenya's Aberdare mountains. Microhabitat data were collected in 127 plots: 37 related to bongo habitat use, 90 from 1 km-spaced grid points representing overall habitat availability and bongo non-presence. We then assessed each SCI's effectiveness for discerning microhabitat variability and bongo habitat selection, using Wilcoxon Rank Sum tests for differences in mean SCI scores among plots divided into 4 vegetation classes, and the Area Under the Curve (AUC) of receiver operating characteristics from logistic regressions. We also examined the accuracy of predicted SCI scores resulting from regression models based on variables derived from a) ASTER imagery processed with spectral mixture and texture analysis, b) an SRTM DEM and c) rainfall data, using the 90 grid plots for model training and the bongo plots as an independent test dataset. Of the five SCIs derived, two performed best: the PCA-derived Canopy Structure Index (CSI) and an additive index summarizing 8 structural variables (AI 8). CSI and AI 8 showed significant differences between 5 of 6 vegetation class pairs, strong abilities to distinguish bongo-selected from available habitat (AUCs = 0.71 (CSI); 0.70 (AI 8)), and predicted scores 60-110% more accurate than reported by other studies using RS to quantify individual microhabitat structural attributes (CSI model R 2 = 0.51, RMSE = 0.19 (training) and 0.21 (test); AI 8 model R 2 = 0.46, RMSE = 0.17 (training) and 0.19 (test)). Repeating the Wilcoxon tests and logistic regressions with RS-predicted SCI values showed that AI 8 most effectively preserved the patterns found with the observed SCIs. These results demonstrate that SCIs effectively characterize microhabitat structure and selection, and boost microhabitat mapping accuracy when combined with enhanced RS image-processing techniques. This approach can improve distribution models and broaden their applicability, makes RS more relevant to applied ecology, and shows that processing field data to be more compatible with RS can improve RS-based habitat mapping accuracy. © 2009 Elsevier Inc. All rights reserved.

King J.D.,Rare Species Conservatory Foundation | Muhlbauer M.C.,P.A. College | James A.,Ministry of Agriculture and the Environment
Zoo Biology | Year: 2011

Asymptomatic captive bred and wild-caught mountain chicken frogs (Leptodactylus fallax) were radiographed for evidence of metabolic bone disease (MBD). All 22 captive bred frogs had multiple folding fractures of long bones, decreased bone density, and cortical thinning, whereas none of the 11 wild-caught frogs had any radiographic evidence of MBD. These findings suggest that the nutritional requirements of L. fallax need to be examined for captive management purposes. © 2010 Wiley-Liss, Inc.

Landolfi J.A.,Loyola University | Miller M.,Rare Species Conservatory Foundation | Maddox C.,Urbana University | Zuckermann F.,Urbana University | And 2 more authors.
Tuberculosis | Year: 2014

Tuberculosis is an important health concern for Asian elephant (Elephas maximus) populations worldwide, however, mechanisms underlying susceptibility to Mycobacterium tuberculosis are unknown. Proliferative responses assessed via brominated uridine incorporation and cytokine expression measured by real-time RT-PCR were evaluated in peripheral blood mononuclear cell (PBMC) cultures from 8 tuberculosis negative and 8 positive Asian elephants. Cultures were stimulated with Mycobacterium bovis purified protein derivative (PPD-B), M. tuberculosis culture filtrate protein (CFP)-10, and Mycobacterium avium PPD (PPD-A). Following stimulation with PPD-B, proliferation was higher (α = 0.005) in positive samples; no significant differences were detected following CFP-10 or PPD-A stimulation. Tumor necrosis factor (TNF)-α, interleukin (IL)-12, and interferon (IFN)-γ expression was greater in samples from positive elephants following stimulation with PPD-B (α = 0.025) and CFP-10 (α = 0.025 TNF-α and IL-12; α = 0.005 IFN-γ). Stimulation with PPD-A also produced enhanced IL-12 expression in positive samples (α = 0.025). Findings suggested that differences in immune cell function exist between tuberculosis positive and negative elephants. Proliferative responses and expression of TNF-α, IL-12, and IFN-γ in response to stimulation with PPD-B and CFP-10 differ between tuberculosis positive and negative elephants, suggesting these parameters may be important to tuberculosis immunopathogenesis in this species. © 2014 The Authors. Published by Elsevier Ltd.

King J.D.,Rare Species Conservatory Foundation | Mechkarska M.,United Arab Emirates University | Meetani M.A.,United Arab Emirates University | Conlon J.M.,United Arab Emirates University
Comparative Biochemistry and Physiology - Part D: Genomics and Proteomics | Year: 2013

Peptidomic analysis was used to compare the distribution of host-defense peptides in norepinephrine-stimulated skin secretions from Xenopus victorianus Ahl, 1924 (also described as the subspecies X. laevis victorianus) and Xenopus laevis sudanensis Perret, 1966 with the previously determined distributions in Xenopus laevis (Daudin, 1802) and Xenopus petersii Bocage, 1895. Peptides belonging to the magainin, peptide glycine-leucine-amide (PGLa), and caerulein precursor fragment (CPF) families were purified by reversed-phase HPLC and characterized by electrospray mass spectrometry. Magainin-P2, PGLa-P1, CPF-P1, CPF-P2, and CPF-P3 previously isolated from X. petersii and structurally different from orthologous peptides from X. laevis, were identified in X. victorianus and X. laevis sudanensis skin secretions whereas the corresponding X. laevis peptides were absent. Magainin-1, identical in X. petersii and X. laevis, was also identified in the secretions. Xenopsin-precursor fragment (XPF) peptides, absent from X. petersii but present in X. laevis skin secretions, were not identified in the X. victorianus and X. laevis sudanensis secretions. The data indicate that X. victorianus and X. laevis sudanensis are more closely related to X. petersii than to X. laevis and support separate species status. The study illustrates the value of analysis of host-defense peptides in the evaluation of taxonomic and phylogenetic relationships between closely related frog species. © 2013 Published by Elsevier Inc.

Michael Conlon J.,United Arab Emirates University | Mechkarska M.,United Arab Emirates University | King J.D.,Rare Species Conservatory Foundation
General and Comparative Endocrinology | Year: 2012

African clawed frogs of the Xenopodinae (Xenopus+. Silurana) constitute a well-defined system in which to study the evolutionary trajectory of duplicated genes and are a source of antimicrobial peptides with therapeutic potential. Allopolyploidization events within the Xenopodinae have given rise to tetraploid, octoploid, and dodecaploid species. The primary structures and distributions of host-defense peptides from the tetraploid frogs Xenopus borealis, Xenopus clivii, Xenopus laevis, Xenopus muelleri, " X. muelleri West" , and Xenopus petersii may be compared with those from the octoploid frogs Xenopus amieti and X. andrei. Similarly, components in skin secretions from the diploid frog Silurana tropicalis may be compared with those from the tetraploid frog Silurana paratropicalis. All Xenopus antimicrobial peptides may be classified in the magainin, peptide glycine-leucine-amide (PGLa), caerulein-precursor fragment (CPF), and xenopsin-precursor fragment (XPF) families. However, the numbers of paralogs from the octoploid frogs were not significantly greater than the corresponding numbers from the tetraploid frogs. Magainins were not identified in skin secretions of Silurana frogs and the multiplicity of the PGLa, CPF, and XPF peptides from S. paratropicalis was not greater than that of S. tropicalis. The data indicate, therefore, that nonfunctionalization (gene silencing) has been the most common fate of antimicrobial peptide genes following polyploidization. While some duplicated gene products retain high antimicrobial potency (subfunctionalization), the very low activity of others suggests that they may be evolving towards a new biological role (neofunctionalization). CPF-AM1 and PGLa-AM1 from X. amieti show potential for development into anti-infective agents for use against antibiotic-resistant Gram-negative bacteria. © 2011 Elsevier Inc.

Estes L.D.,Rare Species Conservatory Foundation | Estes L.D.,University of Virginia | Mwangi A.G.,Rhino Ark Charitable Trust | Reillo P.R.,Rare Species Conservatory Foundation | Shugart H.H.,University of Virginia
Animal Conservation | Year: 2011

Understanding endangered species' spatial ecologies is fundamental to designing effective recovery strategies. Transferable predictive distribution models (PDMs), based on predictors describing the ranges and scales of relevant environmental gradients, can provide this understanding. Using such models for rare species such as the mountain bongo Tragelaphus eurycerus isaaci, an endangered antelope being restored within its endemic range in Kenyan montane forests, is difficult because the species' rarity and challenging terrain complicate data collection. To help overcome data limitations, we used advanced remote sensing (RS) and multiple validation techniques to improve bongo PDMs, which were developed using logistic regression and the information-theoretic approach. We derived predictors using RS, including a new technique for measuring micro-scale vegetation structure, and assessed predictive performance using bootstrapping and independent observations. Terrain ruggedness was the strongest habitat-use predictor, followed by soil moisture availability, distance from law enforcement outposts, vegetation structural complexity, and vegetation edge density. Prediction accuracy generally ranged between 73 and 89%, but terrain ruggedness limited model transferability. The more direct RS-based vegetation predictor improved model transferability. Bongo restoration efforts should focus on high probability areas delineated via a composite of all tested models. The techniques used - particularly RS - enhanced inference quality and the transferability of distribution models, and can be applied to other critical species and ecosystems. © 2011 The Authors. Animal Conservation © 2011 The Zoological Society of London.

Conlon J.M.,United Arab Emirates University | Mechkarska M.,United Arab Emirates University | Ahmed E.,United Arab Emirates University | Leprince J.,University of Rouen | And 3 more authors.
Comparative Biochemistry and Physiology - C Toxicology and Pharmacology | Year: 2011

Five peptides with antimicrobial activity were isolated from norepinephrine-stimulated skin secretions of the tetraploid frog Xenopus clivii Peracca, 1898 (Pipidae). Characterization of the peptides demonstrated that they are structurally similar to magainins (2 peptides), caerulein-precursor fragments, CPF (2 peptides), and xenopsin-precursor fragments, XPF (1 peptide) that have been previously isolated from other species of the genus Xenopus. The magainins and the XPF peptide were active only against the Gram-negative microorganism Escherichia coli whereas the CPF peptides were also active against the Gram-positive Staphylococcus aureus. The most abundant antimicrobial peptide in the secretions, CPF-C1 (GFGSLLGKALRLG ANVL.NH2) inhibited the growth of the Gram-negative bacteria Acinetobacter baumannii, Klebsiella pneumoniae, and Pseudomonas aeruginosa (MIC ≤ 25 μM) suggesting potential for development into an anti-infective agent for use against these emerging antibiotic-resistant pathogens. © 2010 Elsevier Inc.

PubMed | University of Veterinary Medicine Vienna, University of Ulster, Rare Species Conservatory Foundation and CNRS Polymers, Biopolymer and Surfaces Laboratory
Type: | Journal: Comparative biochemistry and physiology. Part D, Genomics & proteomics | Year: 2016

The Uganda clawed frog Xenopus ruwenzoriensis with a karyotype of 2n=108 is one of the very few vertebrates with dodecaploid status. Peptidomic analysis of norepinephrine-stimulated skin secretions from this species led to the isolation and structural characterization of 23 host-defense peptides belonging to the following families: magainin (3 peptides), peptide glycine-leucine-amide (PGLa; 6 peptides), xenopsin precursor fragment (XPF; 3 peptides), caerulein precursor fragment (CPF; 8 peptides), and caerulein precursor fragment-related peptide (CPF-RP; 3 peptides). In addition, the secretions contained caerulein, identical to the peptide from Xenopus laevis, and two peptides that were identified as members of the trefoil factor family (TFF). The data indicate that silencing of the host-defense peptide genes following polyploidization has been appreciable and non-uniform. Consistent with data derived from comparison of nucleotide sequences of mitochrondrial and nuclear genes, cladistic analyses based upon the primary structures of the host-defense peptides provide support for an evolutionary scenario in which X. ruwenzoriensis arose from an allopolyploidization event involving an octoploid ancestor of the present-day frogs belonging to the Xenopus amieti species group and a tetraploid ancestor of Xenopus pygmaeus.

PubMed | University of Kragujevac, University of Cagliari, CNRS Polymers, Biopolymer and Surfaces Laboratory, Rare Species Conservatory Foundation and 2 more.
Type: Journal Article | Journal: Journal of natural products | Year: 2016

Four host-defense peptides belonging to the tigerinin family (tigerinin-1O: RICTPIPFPMCY; tigerinin-2O: RTCIPIPLVMC; tigerinin-3O: RICTAIPLPMCL; and tigerinin-4O: RTCIPIPPVCF) were isolated from skin secretions of the African crowned bullfrog Hoplobatrachus occipitalis. In aqueous solution at pH 4.8, the cyclic domain of tigerinin-2O adopts a rigid amphipathic conformation that incorporates a flexible N-terminal tail. The tigerinins lacked antimicrobial (MIC > 100 M) and hemolytic (LC50 > 500 M) activities but, at a concentration of 20 g/mL, significantly (P < 0.05) inhibited production of interferon- (IFN-) by peritoneal cells from C57BL/6 mice without affecting production of IL-10 and IL-17. Tigerinin-2O and -4O inhibited IFN- production at concentrations as low as 1 g/mL. The tigerinins significantly (P 0.05) stimulated the rate of insulin release from BRIN-BD11 clonal -cells without compromising the integrity of the plasma membrane. Tigerinin-1O was the most potent (threshold concentration 1 nM) and the most effective (395% increase over basal rate at a concentration of 1 M). Tigerinin-4O was the most potent and effective peptide in stimulating the rate of glucagon-like peptide-1 release from GLUTag enteroendocrine cells (threshold concentration 10 nM; 289% increase over basal rate at 1 M). Tigerinin peptides have potential for development into agents for the treatment of patients with type 2 diabetes.

News Article | February 15, 2017
Site: news.yahoo.com

A West African Slender-snouted Crocodile (Mecistops cataphractus) is pictured in its enclosure at the zoo of Abidjan, Ivory Coast September 9, 2016. REUTERS/Luc Gnago ABIDJAN (Reuters) - When conservation biologist Matt Shirley discovered the world's newest crocodile species after years of sloshing through mangroves and swamps from Senegal to Uganda, the elation was tempered by the knowledge that it was on a path to extinction. Now, in its struggle to survive, the West African Slender-snouted Crocodile's fate is tied to a zoo in the heart of Ivory Coast's traffic-choked main city, Abidjan, that itself faced an uncertain future not long ago. "It's very frustrating. But it also gives you a desire to throw your whole body and heart into figuring out what needs to happen to make sure it exists in the future," Shirley told Reuters. "This species in particular, it's my baby." Until just a few years ago, the West African Slender-snouted Crocodile was hiding in plain sight. Before Shirley began his research, the new crocodile and its Central African cousin were considered to be one species. Using genetic testing, he determined they were as different as humans and chimpanzees. Today, no more than 1,500 West African Slender-snouted Crocodile are believed to exist in the wild, scattered across a territory extending from Gambia to Nigeria - an area nearly the size of the continental United States. But in the shade of a stand of broad-leafed trees, some three dozen adults - the largest captive population of the species in the world - lay stretched out in the dust or bobbed motionless in a newly upgraded pond in the Abidjan National Zoo. "It makes it a very critical institution for the future of this species," said Shirley, who works for the Florida-based Rare Species Conservatory Foundation. The zoo already has a breeding programme for the crocodiles and is receiving assistance from partner organisations in the United States. And though a lack of easy access to specialised equipment has forced a certain amount of improvisation, including egg incubators built out of old Coca-Cola refrigerators, survival rates have been remarkably high. "We're roughly around 24 to 25 percent. And even the percentages we're getting in the U.S., this zoo right here will beat them," said Matt Eschenbrenner of the ABQ BioPark Zoo in Albuquerque, New Mexico, which is assisting the programme. Things could easily have been different however. In 2011, following a decade-long political crisis and a contentious presidential election, civil war broke out in Ivory Coast. Soon, gun battles were raging in the neighbourhoods surrounding the Abidjan Zoo. Tia Lama, who has worked there for nearly 25 years, was one of a handful of dedicated employees who braved the violence to feed and care for the animals. "There were personnel who were stepping over dead bodies to go out looking for food. If we didn't, what were (the animals) going to do?" he said. Despite their efforts, by the end of the months-long war, roughly a quarter of the animals had died. Carnivores were hit the hardest. The zoo's lions were wiped out. But the crocodiles survived. "I told myself there must be a secret under the water that kept them alive," Lama said. So far, the zoo's breeding efforts have produced around 40 young crocodiles. Some of them are now two years old, and Shirley is negotiating with the government to reintroduce them into the wild - first in Ivory Coast and then possibly elsewhere in West Africa. "Man depends on nature. If nature disappears, so will humans," said Barnabe Digbe, who heads the Abidjan Zoo's crocodile department. "And so when you are at the heart of a project to protect nature, you can only be happy about it."

Loading Rare Species Conservatory Foundation collaborators
Loading Rare Species Conservatory Foundation collaborators