Laserfiche WebLink
• Minden to the Lexington (Highway 283) bridges. Each census began flying upstream (east to <br />west) along the south side of the main river channel with both observers looking out the <br />passenger side of the aircraft. This provided optimum light conditions such that observers <br />looked away from the rising sun thereby minimizing glare off reflective surfaces. Start points <br />were alternated for each leg to address the concern that one end of the river transect would <br />always be flown earlier than the other end. On the east leg, day one began at Chapman, flew the <br />river west to Minden then flew a predetermined route back to Chapman. Day two began at <br />Wood River, flew the river to Minden, returned along a predetermined route back to Chapman, <br />then flew the rest of the river transect from Chapman to Wood River. The start points for the <br />west leg were Minden and Odessa bridges. Day one began at Minden, flew the river west to <br />Lexington then flew a predetermined route back to Minden. Day two began at Odessa, flew the <br />river to Lexington, returned along a predetermined route back to Minden, then flew the rest of <br />the river transect from Minden to Odessa. When the initial portion of the river transect was <br />completed, one of 7 possible return routes located along the centerline of the main channel and 1, <br />2, and 3 miles north and south of the river respectively was flown with observers looking out <br />opposite sides of the aircraft. <br />Four ground observers were stationed along the survey routes. Communication between <br />the ground observers and the aircraft was accomplished through the use of two -way radios. In <br />the event of a possible Whooping Crane sighting by the air crew, the ground person nearest the <br />sighting was contacted and immediately dispatched to the location in an effort to confirm the <br />identity of the white object. Each technician had a set of color infrared aerial photos of the river <br />• (photos were developed by WEST, Inc. and have been used since October 2001). The photos <br />were inserted in polypropylene sheet protectors that enabled the observer to mark sighting <br />locations on the photo for later reference. Efforts were made to photograph Whooping Cranes <br />from the air using digital cameras. In addition, a GPS reading of the location was taken by air <br />crew. <br />n <br />If a Whooping Crane was located by ground personnel, habitat use and activity <br />monitoring commenced. These observations were continuous until the bird was either lost from <br />view or went to roost for the night. Each Whooping Crane sighting was assigned a unique <br />number and later compared with the U.S. Fish and Wildlife Service's (USFWS) sighting records <br />in Grand Island. A Whooping Crane sighting was defined as: <br />"...the observation of a single whooping crane or a group of whooping cranes that are <br />migrating the <br />through the area. Confirmed sightings in the same general area (within a <br />reasonable distance of daily crane activities) along the Platte and within one to several days of <br />another sighting is assumed to be the same bird/bird group, unless: 1) the number of birds differs, <br />2) the bird(s) constitute a bird/bird group in addition to those already known to be in the general <br />area, or 3) the original birds were observed to migrate from the valley or are known to have <br />moved to a different area of the valley. This assumption is necessary because individual cranes <br />cannot be distinguished; very few birds are marked and continuous surveillance of a crane or <br />crane group using the study area is not possible." (Aransas — Wood Buffalo Population <br />Whooping Crane Contingency Plan 2006, Whooping Crane Committee of the Central Flyway <br />Council). <br />Final Spring 2008 Whooping Crane Monitoring Report 2 <br />6/20/2008 <br />