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With all the poor reproduction success, one must what is wrong? Why are sandhill cranes doing well in Wisconsin and across the U.S., while reintoduced Whooping Cranes fail to naturally keep their population viable? The obvious answer is Whooping Cranes are no Sandhill Cranes, a larger size, longer time to maturity, and possibility small clutch size makes all the difference. A turtle example would be the difference between Northern Painted Turtles and Blanding's turtles, why is one doing well in Wisconsin, while the latter's population is declining. The Blanding's turtle has a longer time to maturity and larger body size, apparently that makes all the difference in the world. Painted turtles live in many types of aquatic habitats, while Blanding's turtles perfer swallow aquatic habitats with soft bottoms. Sandhill Cranes seems to tolerate fragmented landscapes, the same might not hold true for Whooping Cranes. The only country that whooping cranes currently breed successfully is Canada, it has a road density of 0.16 mi/mi². The U.S. has a road density of 1.2 mi/mi² and Necedah NWR has a road density of 1.83 mi/mi². Ecological effects of roads on animal populations are habitat loss, reduced habitat quality, mortality and reduced connectivity (Forman 2003). Are National Wildlife Refuges support a whooping cranes? Are they too fragmented, too small? The major problem with Wisconsin/Florida migratory population is nest abandonment. During the last several years (2005 to 2011), very few nests were successfull and even fewer chicks survived to fledging. In 2008 Dr. Richard Urbanek saw some anecdotal evidence that black flies were the cause of the nest abandonments. Research done in 2009 by Richard King (Necedah NWR Biologist) showed more insights to the black fly problem but the "the data was not completely conclusive" since four of the nests did not fit into the the (Stehn 2009). The research does suggest that black flies are causing the nest abandoment problem. A bactercide called BTi (approved by EPA) is being considered for use at Necedah NWR and surrounding areas to reduce the number of black flies. WCEP is not talking the nest abandonment problem lightly, research is being done to find some answers. Some hypotheses for nest failures/abandoment include: effects of captivity, infertility, predators, phenology, food availability (both breeding & wintering grounds), weather and black flies. Phenology could be another big factor, since the source of the captive population is Aransas/Buffalo Woods population. After BTi treatment in 2011, the WCEP breeding season was still a disappointment, 4 chicks were hatched (out of 22 nests), but none of the chicks survived to fledge. Maybe Horicon NWR and White River Marsh State Wildlife Area will provide success for WCEP, the project that keeps on ticking.
Since the discontinuation of the Florida nonmigratory project, reintroducing a nonmigratory flock in Louisana is the next WCEP experiment. Before the Wisconsin/Florida migratory project got started, Louisana had the best sites for Whooping Crane release, since it is with in the central core of historical Whooping Crane range and the last nonmigratory population was there. One of the reasons why Florida was choosen was to keep the reintroduced population as far away from the Woods Buffalo/Aransas population. This was in fear of any sort of captive diseases (esp. Infectious Bursal Disease) being introduced from breeding centers to the wild population and abnormal behaviors from captive birds being introduced to the wild population. Invasive exotic diseases such as Exotic Newcastle Disease and West Nile virus have had detrimental effects on native wildlife and with the very little we know about wildlife diseases, fears of disease outbreaks were well justified. On March 14th 2011, 10 Whooping Cranes were released at White Lake, by November 3rd, 5 of them were dead (2 missing, 1 euthanized due to Aspergillosis & 2 shot by juveniles with guns).
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