Barrier Island Population along the U.S. Atlantic and Gulf Coasts

2011 ◽  
Vol 27 (2) ◽  
pp. 356 ◽  

2021 ◽  
Author(s):  
◽  
Gemma Bowker-Wright

<p>Pateke/brown teal (Anas chlorotis) have experienced a severe population crash leaving only two remnant wild populations (at Great Barrier Island and Mimiwhangata, Northland). Recovery attempts over the last 35 years have focused on an intensive captive breeding programme which breeds pateke, sourced almost exclusively from Great Barrier Island, for release to establish re-introduced populations in areas occupied in the past. While this important conservation measure may have increased pateke numbers, it was unclear how much of their genetic diversity was being retained. The goal of this study was to determine current levels of genetic variation in the remnant, captive and re-introduced pateke populations using two types of molecular marker, mitochondrial DNA (mtDNA) and microsatellite DNA. Feathers were collected from pateke at Great Barrier Island, Mimiwhangata, the captive breeding population and four re-introduced populations (at Moehau, Karori Wildlife Sanctuary, Tiritiri Matangi Island and Mana Island). DNA was extracted from the base of the feathers, the mitochondrial DNA control region was sequenced, and DNA microsatellite markers were used to genotype individuals. The Great Barrier Island population was found to have only two haplotypes, one in very high abundance which may indicate that historically this population was very small. The captive breeding population and all four re-introduced populations were found to contain only the abundant Great Barrier Island haplotype as the vast majority of captive founders were sourced from this location. In contrast, the Mimiwhangata population contained genetic diversity and 11 haplotypes were found, including the Great Barrier Island haplotype which may have been introduced by captive-bred releases which occurred until the early 1990s. From the microsatellite results, a loss of genetic diversity (measured as average alleles per locus, heterozygosity and allelic richness) was found from Great Barrier Island to captivity and from captivity to re-introduction. Overall genetic diversity within the re-introduced populations (particularly the smaller re-introduced populations at Karori Wildlife Sanctuary, Tiritiri Matangi Island and Mana Island) was much reduced compared with the remnant populations, most probably as a result of small release numbers and small population size. Such loss of genetic diversity could render the re-introduced populations more susceptible to inbreeding depression in the future. Suggested future genetic management options are included which aim for a broader representation of genetic diversity in the pateke captive breeding and release programme.</p>



Reproduction ◽  
2014 ◽  
Vol 147 (6) ◽  
pp. 855-863 ◽  
Author(s):  
Heather J Hamlin ◽  
Russell H Lowers ◽  
Satomi Kohno ◽  
Naoko Mitsui-Watanabe ◽  
Haruna Amano ◽  
...  

Comparatively, little data are available detailing the geographic variation that exists in the reproductive endocrinology of adult alligators, especially those living in barrier islands. The Merritt Island National Wildlife Refuge (MI) is a unique barrier island environment and home to the Kennedy Space Center (FL, USA). Seasonal patterns of sex steroids were assessed in adult female American alligators from MI monthly from 2008 to 2009, with additional samples collected at more random intervals in 2006, 2007, and 2010. Plasma 17β-estradiol and vitellogenin concentrations peaked in April, coincident with courtship and mating, and showed patterns similar to those observed in adult female alligators in other regions. Plasma concentrations of progesterone, however, showed patterns distinctly different than those reported for alligator populations in other regions and remained relatively constant throughout the year. Plasma DHEA peaked in July around the time of oviposition, decreased in August, and then remained constant for the remaining months, except for a moderate increase in October. Circulating concentrations of DHEA have not been previously assessed in a female crocodilian, and plasma concentrations coincident with reproductive activity suggest a reproductive and/or behavioral role. Interestingly, plasma testosterone concentrations peaked in May of 2008, as has been shown in female alligator populations in other regions, but showed no peak in 2009, demonstrating dramatic variability from year to year. Surveys showed 2009 to be particularly depauperate of alligator nests in MI, and it is possible that testosterone could serve as a strong indicator of breeding success.



2021 ◽  
Author(s):  
◽  
Gemma Bowker-Wright

<p>Pateke/brown teal (Anas chlorotis) have experienced a severe population crash leaving only two remnant wild populations (at Great Barrier Island and Mimiwhangata, Northland). Recovery attempts over the last 35 years have focused on an intensive captive breeding programme which breeds pateke, sourced almost exclusively from Great Barrier Island, for release to establish re-introduced populations in areas occupied in the past. While this important conservation measure may have increased pateke numbers, it was unclear how much of their genetic diversity was being retained. The goal of this study was to determine current levels of genetic variation in the remnant, captive and re-introduced pateke populations using two types of molecular marker, mitochondrial DNA (mtDNA) and microsatellite DNA. Feathers were collected from pateke at Great Barrier Island, Mimiwhangata, the captive breeding population and four re-introduced populations (at Moehau, Karori Wildlife Sanctuary, Tiritiri Matangi Island and Mana Island). DNA was extracted from the base of the feathers, the mitochondrial DNA control region was sequenced, and DNA microsatellite markers were used to genotype individuals. The Great Barrier Island population was found to have only two haplotypes, one in very high abundance which may indicate that historically this population was very small. The captive breeding population and all four re-introduced populations were found to contain only the abundant Great Barrier Island haplotype as the vast majority of captive founders were sourced from this location. In contrast, the Mimiwhangata population contained genetic diversity and 11 haplotypes were found, including the Great Barrier Island haplotype which may have been introduced by captive-bred releases which occurred until the early 1990s. From the microsatellite results, a loss of genetic diversity (measured as average alleles per locus, heterozygosity and allelic richness) was found from Great Barrier Island to captivity and from captivity to re-introduction. Overall genetic diversity within the re-introduced populations (particularly the smaller re-introduced populations at Karori Wildlife Sanctuary, Tiritiri Matangi Island and Mana Island) was much reduced compared with the remnant populations, most probably as a result of small release numbers and small population size. Such loss of genetic diversity could render the re-introduced populations more susceptible to inbreeding depression in the future. Suggested future genetic management options are included which aim for a broader representation of genetic diversity in the pateke captive breeding and release programme.</p>



2021 ◽  
pp. 1-20
Author(s):  
Jennifer L. Britton ◽  
Christian Hunold

Abstract This multispecies ethnography investigates how free-roaming ponies and humans participate in the production of “pony wildness” on Assateague Island, a barrier island located off the U.S. mid-Atlantic coast. The bordering practices of ponies intersect with the bordering practices of people to generate a relational conception of pony wildness that incorporates in people-pony relations a desire for intimacy with respect for autonomy, in a multifunctional landscape managed both as wilderness and as a beach tourism destination. This notion of pony wildness includes nonhuman charisma, fluidity, and managing human visitors. We conclude by discussing how the fluidity of pony wildness can help us think more imaginatively about other contexts in which communities of free-roaming nonhuman animals share space with human communities.



2020 ◽  
pp. 1-13
Author(s):  
MATT J. RAYNER ◽  
AYLA L. VAN LOENEN ◽  
LARA D. SHEPHERD ◽  
ILINA CUBRINOVSKA ◽  
R. PAUL SCOFIELD ◽  
...  

Summary Cook’s Petrel Pterodroma cookii is an endemic New Zealand seabird that has experienced a large range decline since the arrival of humans and now only breeds on two offshore islands (Te Hauturu-o-Toi/Little Barrier Island and Whenua Hou/Codfish Island) at the extreme ends of its former distribution. Morphological, behavioural, and mitochondrial cytochrome oxidase 1 (CO1) sequence data led a previous study to recognise the two extant populations as distinct conservation management units. Here, we further examine the genetic relationship between the extant populations using two nuclear introns (β-fibint7 and PAX). Using one mitochondrial locus (CO1), we also investigate the past distribution of a single nucleotide polymorphism (SNP) that differentiates the modern populations using bone and museum skins sourced from within its former range across New Zealand’s North and South Islands. We found significant population genetic structure between the two extant Cook’s Petrel populations for one of the two nuclear introns (β-fibint7). The mitochondrial DNA CO1 analysis indicated that the SNP variant found in the Codfish Island population was formerly widely distributed across both the North and South Islands, whereas the Little Barrier Island variant was detected only in North Island samples. We argue that these combined data support the recognition of the extant populations as different subspecies. Previous names for these taxa exist, thus Cook’s Petrel from Little Barrier Island becomes Pterodroma cookii cookii and Cook’s Petrel from Codfish Island becomes P. c. orientalis. Furthermore, we suggest that both genetic and non-genetic data should be taken into consideration when planning future mainland translocations. Namely, any translocations on the South Island should be sourced from Codfish Island and future translocations on the North Island should continue to be sourced from Little Barrier Island only.



Author(s):  
R. D. Heidenreich

This program has been organized by the EMSA to commensurate the 50th anniversary of the experimental verification of the wave nature of the electron. Davisson and Germer in the U.S. and Thomson and Reid in Britian accomplished this at about the same time. Their findings were published in Nature in 1927 by mutual agreement since their independent efforts had led to the same conclusion at about the same time. In 1937 Davisson and Thomson shared the Nobel Prize in physics for demonstrating the wave nature of the electron deduced in 1924 by Louis de Broglie.The Davisson experiments (1921-1927) were concerned with the angular distribution of secondary electron emission from nickel surfaces produced by 150 volt primary electrons. The motivation was the effect of secondary emission on the characteristics of vacuum tubes but significant deviations from the results expected for a corpuscular electron led to a diffraction interpretation suggested by Elasser in 1925.



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