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  • WCEP: Whooping Crane Nest Productivity Studies
    experiment does not call for long term suppression of black flies in the area Nest Monitoring and Hypothesis Testing Going into the 2009 nesting season several theories were developed to investigate the nest abandonment observed in previous years Seven factors potentially contributing to limited whooping crane reproduction were tested Those factors included limited food resources nest disturbance inexperience among nesting pairs incubation delays nest habitat characteristics and harassment by biting insects including black flies The following are explanations of some of the theories and the studies that were conducted during the 2009 nesting season to test those theories Limited Food Resources This study examined the theory that incubating birds were nutritionally stressed so much so that the appearance of numerous prey items triggered by rising temperatures e g the sudden appearance of large numbers of frogs caused them to leave their nests to seek food Researchers observed what the birds were eating and the habitat they occupied while foraging Additional sampling was conducted to determine what food items were available to the cranes at Necedah NWR whether they ate them or not At least seven whooping crane nests were monitored with either cameras or observers in blinds collecting information on nesting and non breeding cranes at timed intervals to determine the role of energy balance on nest abandonment Supplemental food was provided to at least four of the seven nesting pairs to see if providing additional food prevented nest abandonment Harassment by Biting Insects Whooping cranes eggs covered with black flies Photo by USFWS Richard Urbanek Another theory of the cause of nest abandonment is that incubating birds were unable to tolerate the abundant blood feeding black flies that emerged in large numbers with the first significant warm weather Researchers observing nesting pairs in 2008 noted a correlation between the emerging black fly adults and the period of nest abandonment Incubation Delays Another explanation for the nest abandonments is that they were not abandonments but incubation delays When both parents are absent from the nest other than for nest exchanges it is considered delayed incubation Pairs on Necedah have left nests for as long as three days then returned to again incubate It is possible that pairs may be delaying incubation rather than abandoning nests During the 2009 nest season eggs were left in nests when both parents were missing to test whether they would return to incubate Results from the Nest Monitoring Studies Results from the 2009 nesting studies did not provide sufficient data to indicate whether black flies were causing the cranes to abandon incubation before eggs hatched Observers did note that in some cases the abundance of black flies near crane nests appeared to be much higher than would be expected compared to levels monitored elsewhere in the refuge during the same time period The results of the 2009 nesting studies are presented below with the following cautions Studies are unlikely to result in conclusive evidence of causes of nest failure after only one study season Scientific

    Original URL path: http://www.bringbackthecranes.org/technicaldatabase/NestProductionStudies_March2011.html (2016-05-02)
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  • WCEP: Bti
    must be ingested by an insect larva where the crystal dissolves in the gut and converts the protoxins to highly toxic endotoxins These endotoxins bind to gut receptors perforating the membrane and result in paralysis starvation and ultimately death of the insect Specificity The properties of the Bt crystal vary between strains of Bt and are responsible for their specificity One aspect that affects specificity is pH Insects can have widely varying ranges of pH within their guts In order for the endotoxin of a specific strain of Bt to be activated the pH level within the gut must be within a very specific range If the gut is too acidic the toxin will dissolve along with the crystal too basic and the crystal won t dissolve enough to release the toxin which will pass through the organism s stomach unactivated The gut of mosquitoes and black flies where Bti endotoxins are activated are much more alkaline than most animals Another layer of specificity lies within the receptors of the gut membrane where the endotoxins bind These receptors are species specific so even when endotoxins are properly activated they can only cause damage to those species which possess suitable binding sites Effects to Nontarget Species Bti is highly toxic to black flies and mosquitoes and has been found to have activity against some species of midge No other insect species including other dipterans have been found to be susceptible to Bti toxicity No effects to birds mammals fish or other invertebrate species exposed to Bti have been detected Temporary indirect effects to insectivorous species may occur due to the loss of target insects from the community though numerous field and mesocosm studies in flowing water systems found no effects to species abundance richness or diversity following the application of Bti

    Original URL path: http://www.bringbackthecranes.org/technicaldatabase/Bti.html (2016-05-02)
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  • WCEP: External Review Report - March 2010
    a viable wild population of whooping cranes at relocation sites whether current or future Habitat based studies on natural Aransas Wood Buffalo as well as current Necedah NWR and potential reintroduction sites should be conducted Captive Whooping Crane Management The goals of the current management strategy for the production of whooping cranes have been to produce as many chicks per year as is feasible thus management has focused on artificial insemination artificial incubation and artificial rearing The program has been successful in maintaining a viable captive flock and providing 25 30 chicks per year for the WCEP efforts The captive population has been managed appropriately over its lifetime using the most up to date demographic and genetic tools available to it at each phase Recent molecular analyses suggesting that founders may be more related than hitherto believed which could limit future pairings are preliminary and would greatly benefit from additional data collection and analysis There are increasing demands for larger cohorts of whooping crane chicks to expand the DAR program initiate a dedicated parent rearing PR study and begin planning for a proposed release in Louisiana to create a third non migratory flock Available data indicate that chick production at the Patuxent Wildlife Research Center WRC and International Crane Foundation ICF is at or very near capacity which will clearly limit WCEP s ability to allocate a sufficient number of chicks to the aforementioned programs The approaches used to produce eggs and rear and train chicks costume rearing have proved successful in that enough chicks are produced annually to support current reintroduction program needs On the other hand such success likely has limited further experimentation to improve the breeding and rearing of cranes We strongly support the new effort to look at the impact of parent rearing on survival migration and reproductive success in the wild and to evaluate whether there are other more cost effective methods for producing and rearing chicks The Review Team has noted the existence of some underlying assumptions that may never have been tested and have had a major impact on decision making and implementation of activities Examples include the assumptions that socialization of chicks into groups has no impact on later survival and reproduction habituation to humans without costumes during rearing will have a negative effect on survival and behavior and wildness and fear of humans is critical for survival and successful reproduction We believe that these assumptions need explicit testing Recommendations Allocate a majority of chicks produced over the coming five years to DAR and PR programs with the UL program being allocated a sufficient number of chicks to permit their continued activity and for purposes of comparative study Consider costs and benefits of using eggs obtained from the Aransas Wood Buffalo population to satisfy future demand and increase genetic diversity of the captive flock Identify mechanisms by which egg production across existing and potential WCEP partners can be increased to accommodate annual demand Determine the age at which imprinting to humans may no longer be a problem initially using sandhill cranes as a model and consider the implications for crane management of no longer implementing costume rearing through and beyond release Continue to use all data at hand pedigrees from leg banding and molecular information in combination with proper demographic and population genetic analysis i e master planning to ensure responsible management of the captive whooping crane resource If feasible expand molecular analysis of the captive whooping crane studbook i e larger number of microsatellite loci to improve estimates of founder relatedness in the captive population Wild Whooping Crane Management Management of juvenile whooping cranes during their first migration following release is directly related to their release strategy UL birds are controlled during migration while DAR and eventually parent reared PR birds will be free to migrate as they choose Depending on their release protocol UL DAR or PR juveniles are either allowed to winter in sites they select or are managed in penned areas on St Marks and Chassahowitzka NWR s in Florida Few data are available or have been evaluated to identify factors related to management of free flying cranes that may affect reproduction in whooping cranes at Necedah NWR making it difficult to evaluate which management techniques are most biologically successful and cost effective One of the current requirements of establishing an EMP is to maintain complete separation between a population established from captive bred birds from the wild naturally occurring Aransas Wood Buffalo Population AWBP of whooping cranes The Review Team believes that it would be beneficial to conduct a formal risk assessment concerning the likelihood of a catastrophic disease transmission event if the populations meet and evaluate the potential impact on population viability for both populations from disease transmission versus the benefits of genetic and demographic augmentation from flock mixing We are aware that relaxing the requirement of separation of the AWBP and any reintroduced population would require re designating the EMP birds which are now considered an experimental non essential population under Section 10 j of the ESA which requires geographic distinction of the populations Canadian Wildlife Service and U S Fish and Wildlife Service 2007 however the Review Team thinks it might be time to begin to explore the implications of a future re designation Recommendations Develop and conduct scientifically sound observational and experimental studies of the EMP within an adaptive management framework to investigate factors affecting whooping crane breeding ecology and success Conduct comparative studies of the breeding ecology migratory behavior energetic requirements and habitat use of whooping cranes of the AWBP and the EMP to better understand whooping crane ecology and the affects of EMP management on breeding success Conduct rigorous scientific comparisons of the behavioral ecology survival and reproductive success across existing and proposed rearing techniques UL DAR PR over a period of at least seven years to determine which technique results in the highest levels of whooping crane recruitment and successful reproduction Additionally use the results from comparative rearing studies to

    Original URL path: http://www.bringbackthecranes.org/whoweare/ExternalReviewMarch2010.html (2016-05-02)
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  • WCEP: Splitting the Current Year Cohort of Whooping Cranes
    YouTube Twitter Splitting the Current Year Cohort Current Year Cohort will Winter in Two Separate Groups For the first time the new class or cohort of whooping cranes will winter in two different locations On January 14 at a stopover in Jefferson County Florida the 2009 cohort was divided into two carefully selected groups On January 17 2009 one group of 7 young whooping cranes was led to a newly constructed pen at St Marks National Wildlife Refuge NWR The remaining seven whooping cranes proceed to their ultimate destination at Chassahowitzka NWR where they arrived on January 23 Splitting the cohort and establishing another wintering site was done in response to a catastrophic storm that killed most of the 2006 cohort Dividing the current year cohort into groups that winter at different sites should prevent another loss of an entire year class due to one catastrophic event whether it be weather predation poaching or something else Below are documents that provide explanations and more details on the decision to split the current year class and the decision to use St Marks National Wildlife Refuge as the other wintering site Whooping Cranes Arrive at St Marks Refuge Nov 17 2009 Ultralight

    Original URL path: http://www.bringbackthecranes.org/technicaldatabase/splitflock.html (2016-05-02)
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  • WCEP: SUMMARY OF FLORIDA RELEASE SITE ANALYSIS
    measures to mitigate risk but unclear if measures implemented at St Marks would reduce risk to Chassahowitzka levels Reduce risk of accidental shooting by hunters Risk from accidental shooting by hunters is very low in both cases though slightly higher at St Marks because of land access Both pen sites are within closure areas where hunting would be prohibited Maximize site access for project staff under all conditions St Marks is more accessible under all conditions Reduce risk from disease Not a main deciding factor because there is not a significant difference between the two sites on this factor Both sites are tidally influenced marsh systems though flushing of site by tides is better at Chassahowitzka Maximize access to needed resources water food at pen site Supplemental forage blue crabs snails fiddler crabs are available at both sites Possibly more forage available at St Marks if cranes use the coastal marshes but not a significant difference between sites because needed resources would be provided at both sites Minimize exposure to powerlines No significant difference between sites Minimize exposure to bioaccumulating toxins No significant difference between sites OBJECTIVE 2 Maximize learning normal behaviors and survival in wild Maximize learning normal roosting Similar with some differences Facilitate appropriate habitat for cranes to learn predator avoidance behavior The differences between the two sites were unclear distance to treeline greater at St Marks more water for roosting at Chassahowitzka Optimal roosting conditions were created at Chassahowitzka through the construction of an oyster bar and similar action is proposed for St Marks The qualities of each site were hard to characterize and much debated unresolved Maximize learning normal foraging behavior Possibly more natural forage available at St Marks Because food is 95 crane chow provided at the pen site under current protocols there is no significant difference between sites Maximize opportunities to socialize bond with other whooping cranes Fifty per cent of the current population has been wintering within 80 km of Chassahowitzka and 60 within 100km St Marks is located along the Sandhill crane migration route into Florida and is 100 km northwest from the core of the existing wintering population St Marks is 50 km west of Hixtown Swamp and San Pedro Bay known wintering locations Will release at St Marks affect the cranes ability to find each other to migrate together and find potential mates Ultimate implications are unknown initially fewer opportunities for pair formation on Wintering grounds by moving to new site Promote use of most suitable winter habitat in future years A GIS analysis indicates 430 000 acres of crane habitat within 65 km of Chassahowitzka 210 000 acres of crane habitat within 65 km of St Marks There is a possibility that cranes will use salt marsh habitat at St Marks but unknown Currently there is more preferred habitat available near Chassahowitzka Central Florida is predicted to be one of the highest growth areas of Florida Migratory birds can shift around and long term could respond to development by

    Original URL path: http://www.bringbackthecranes.org/technicaldatabase/summaryFLreleasesiteanalysis.html (2016-05-02)
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  • WCEP: June 12 , 2007 Statement on
    3 03 and 17 03 that are full siblings brother and sister Since the egg produced in captivity was known to be fertile WCEP was capitalizing on the potential for a chick to hatch from that wild nest We have found that whooping cranes nearly always return to a nest and continue to incubate after human manipulation of eggs like this meaning there was good potential for the egg to hatch successfully becoming the third wild whooping crane to hatch in Wisconsin in more than a century The egg removed from the nest was found to be infertile Unfortunately the cranes flushed from the nest and did not return Biologists then removed the captive produced egg replaced it with a dummy egg and returned the captive produced egg to the International Crane Foundation where it was expected to hatch soon The resulting chick will become part of the Direct Autumn Release of whooping cranes this fall Crane chicks produced from full sibling pairs are likely to show low survivability due to the expression of genetic mutations if they do survive to breeding age they are unlikely to breed successfully One of the goals of any reintroduction is to try to

    Original URL path: http://www.bringbackthecranes.org/newsroom/2007/stmnt-061207.html (2016-05-02)
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  • WCEP: Loss of Whooping Cranes at Chassahowitzka National Wildlife Refuge After Storms Hit Central Florida
    at the Chassahowitzka National Wildlife Refuge The cranes died as a result of the storms that swept through central Florida during the evening and early morning of February 1 and 2 We are in the initial stages of determining the cause of death of the 18 whooping cranes which comprised the ultralight led Class of 2006 and arrived at the Chassahowitzka NWR in mid January Following standard protocol WCEP personnel checked on the cranes the evening of February 1 Due to the magnitude of the storm and the location of the pensite personnel were unable to safely check on the cranes until this afternoon at which time the birds were discovered dead in their enclosure While this is a setback for the whooping crane reintroduction project WCEP has faced challenges in the past and we plan to move forward with our effort to return this highly imperiled species to its historic range in eastern North America My heart is aching both for the young birds we lost and for the dedicated people who devote so much of themselves to this project only to see the cranes lives end in this devastating manner These birds were the start of a new

    Original URL path: http://www.bringbackthecranes.org/newsroom/2007/nr-020207.html (2016-05-02)
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  • WCEP: Whooping Crane Arrival at Halpata
    to older cranes visiting the pen at Chassahowitzka and causing trouble with the younger birds Chassahowitzka NWR has been used as the release site for WCEP whooping cranes since the beginning of the project in 2001 Chassahowitzka was selected because the pen site is not accessible by the public naive juveniles can be effectively protected from predators physical facilities are ideal and movements of juveniles can be controlled because habitat conditions limit dispersal Because of tidal fluctuations salinity unstable or rocky bottom substrates and general habitat dominance by needlerush this area actually offers poor habitat for wintering whooping cranes Many returning older Whooping cranes routinely visit the pen site each year but do not remain in the area and instead winter in other habitats located inland This pattern has been advantageous to the reintroduction by allowing this release site to be used year after year In the past the new class of ultralight led young of year chicks sometimes arrived at Chassahowitzka while the adult Whooping cranes were still passing through during their fall migration The activity and food at the pen site often encouraged the older cranes to stay and they were at times overly aggressive towards the younger birds and interfered with their access to the food provided for their use To address this problem WCEP found a second site and constructed a new pen near Dunnellon 26 miles to the northeast of the Chassahowitzka pen site This property is owned by the South West Florida Water Management District and known as Halpata Tastanaki Preserve This site was established to hold the chicks until the older birds have left the Chassahowitzka pen or possibly as a new site where the birds would spend the winter if older birds remained at Chassahowitzka Halpata is now used annually as a

    Original URL path: http://www.bringbackthecranes.org/technicaldatabase/projectupdates/2009/halpata22Jan2009.html (2016-05-02)
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