Tulsa Audubon Society
Zink Island and 71st Street Island
Least Tern Breeding Survey
byColin P Davy
Least Tern Observers
LEAST TERN BREEDING SURVEY - Summer 2003
by Colin P Davy
The Least Terns have spread along the river to nest in areas which they appear to prefer over Zink Island; more birds appear to be using the 71st. Street sandbanks, but the width of the river precludes an accurate accounting from the eastern shore.
The purpose of the breeding survey is to ascertain the success of the current year breeding season with previous years and so assist the local office of the US Fish and Wildlife Services, with whom we continue to enjoy a useful and friendly relationship of many years, to determine the progress of this endangered and protected species. From the count made by our team of volunteer observers, it would appear that the numbers continue to decline. However, it has been seen that the Least Terns have spread along the Arkansas River to enjoy new areas where a combination of additional silting of the river bed and low water levels has created nesting areas apparently more attractive to the Terns than the original location. Some of these new areas appear to be very susceptible to inundation in the event of small changes in the level of the river. Fortunately, there were no events of this sort during the present season.
The survey extended from May 27th. Through to August 2nd. In the Zink Island area.
Early rainfall in the Tulsa area and the large number of Canada Geese gathering in the Zink Island area created ideal conditions for a large growth of vegetation. This not only made it difficult for our observing team, but also seemed to deter the birds from nesting on the island.
The sand bank south of the 71st. Street bridge has extended in area in a direction towards the west bank of the river since last year. Officers of the US Fish and Wild-Life Services reported more birds, to be nesting on the western side of the bank than we could see from our observing position in Helmerich Park. The numbers we counted being much lower than those made by USF&WS officers visiting the area by boat, it was decided to discontinue our observations in this area from July 7th.
The author tried to find an alternative observation point, but it was much too dangerous to attempt to park on the south side shoulder of the bridge and no access by public road could be found on the west bank of the river.
One of the new areas where the Terns nested is the reach contained between the bridges close to 51st. and 41st. Streets. Unfortunately there is no convenient car parking space in this area. And here also, the vegetation on the river bank makes observation and an accurate count difficult. In order to obtain an accurate number, an observer needs to be able to swing their binoculars and count in one steady sweep, rotating either upstream or downstream.
On a more positive note, three events are reported here for this year, two of which may have given some indirect free publicity to our mission and hopefully educated the general public to the importance of allowing the Least Tern to continue to enjoy access to their habitat along the river.
On June 30th. Volunteers, including our tern observers, from the chapter assisted officers of the FW&S to round up no fewer than 213 Geese from the Zink Island area that were then transported to a new home further south. The operation took some two-and-a-half hours which involved the volunteers in helping to surround the flock and gently encourage them into a containment area from where they were loaded into trailers for their journey south. Hopefully this will relieve the pressure on the Zink Island area for next season.
A local TV station - KOTV, a CBS affiliate - in reporting certain aspects of the new “Vision 2025 plan” gave a news segment, broadcast on both the 6 and 10pm news, and repeated on Cox cable Channel 53 several times in the same evening, in which Mr. Kevin Stubbs of the F&WLS was interviewed concerning the possible affects of two more low water dams proposed under the plan . Mr Stubbs was able to discuss the possible loss of Least Tern breeding habitat caused by such developments and so alert and perhaps educate the listening public to an environmental issue that could affect a threatened species found within our city and county.
The other occurrence involved a sad happening when persons, possibly ignorant of, and in contravention of the “Migratory Bird Treaty Act of 1918”, collected some Least Tern eggs from a sandbank in the river. Shortly afterwards, some eggs started to hatch and they finished up being brought to the home of our member, and one of this season’s volunteers, Ms. Gail Storey, who as you all know is a licensed wildlife rehabilitation officer. The story was reported on the front page of “The Tulsa World” in their morning edition of Thursday August 7. The publicity obtained was truly an example of “an ill wind that blows some good” and we hope that more citizens are now aware of the Least Terns and that to interfere with their nests and eggs is a serious Federal offence.
In a follow on article, we learned that Gail had successfully raised four birds from five which hatched out of eight eggs brought to her home. The four birds are now to be seen in the zoo at Fort Worth., and we should congratulate and thank Gail for her patient efforts and devotion to raising these orphaned birds.
I would like to thank our volunteer team which included Jo Lloyd, Gail Storey, Aline Romero, Bob Harwood, and Art Browning for their help and support .
We could have used a larger roster of volunteers, even on an “on-call” basis this year, as Aline had to drop out, due to the summer heat . We were unable to cover every weekday and our volunteer’s vacation plans and personal activities left days throughout the season when counts simply could not be made
The overall figures obtained from this effort at Zink Island appear to bear no meaningful relationship to the number of birds seen flying over a six-mile stretch of the river and simply confirm the continued decline in the number using Zink Island.
The Board should therefore consider:-
1. Are the efforts, made to count tern, producing any valid result.
2. Should we try to cover the area from Zink Island down to 71st. Street ? This will involve a six-mile walk assuming sufficient volunteers are available to make car pick up possible?
3. How can we interest and obtain more support from members willing to volunteer their time, and who are physically able to carry out this task in the summer heat
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