From Gary Huschle - Agassiz National Wildlife Refuge
Biologist
What we have planned:
We have ordered 4 satellite transmitters for American bittern that we will put
on previously radioed birds in late July or August. Microwave has not promised
that they will be able to fill the order by July 15 so it may get put off 1
year. This is experimental in collar design, transmission sequence, and location
success. Our objective is to determine migration timing, route and wintering
area. Two birds from Agassiz and two from central Wisconsin would be tagged. The
transmission sequence this year will be once every 10 days in July and August,
once every third day in September through November, once every 10 days during
the winter, and once every 4 days in April and May. Based on this year's results
and finding money, modifications will be made and intend to tag additional birds
next year. This would include birds from a new study site near Lac qui Parle WMA
and possibly in the state of Michigan. Juvenile birds may be tagged in the
second year as we have not had any returning juveniles in the four years
previous to this.
Due to the small battery on these bird collars only 56 days of transmission are
possible. The satellite time from Argos should only cost $600.00. The
transmitters are $2950.00. The wolf collars are designed to last two years.
Gary Huschle
1938 and 1939 are the American bitterns tagged on Agassiz NW
1/10/99
Attached are a few locations. The transmitters are turning back to transmissions
at only every 10 days so there won't be as many now.
Gary
-----Original Message-----
From: gary_huschle
Sent: Wednesday, April 21, 1999 1:01 PM
Subject: Bittern Locations
Jim and Becky:
We have finally received a location on 1938 in migration back north. The April
18/19 location I think (looking at the big wall map) is in west central Iowa. It
is too bad that there were so many ???? locations. This may be related to flying
and not enough transmissions received at a new location. In reviewing some of
the data from last fall it appeared that while the bird was actually flying may
result in ???? locations. This is contrary to what I expected. The bird is up in
the air, no vegetation or terrain problems so I thought in flight locations
would be strong signals. It may have to deal with the antenna orientation.
1940 is still not transmitting. My calculation of the switchback to every 4 days
was April 16. So it does not appear to be going to come back into operation.
Funding this year will allow us to purchase 4 satellite radios for this year.
These will be placed on 4 adult birds again this year to further evaluate
technique and adult migration. Funding may come together for 2000 to purchase 10
or 12 radios. This will allow the next step-- juvenile dispersal and migration!
We will be trapping bitterns after May 1.
Gary
-----Original Message-----
From: gary_huschle
Sent: Friday, May 28, 1999 4:49 PM
Subject: locations
Jim:
Not much good on 1938. I have included 1941 locations. This is the other bird
that wintered in Louisiana. If your students have time to plot these I would
like to know the locations by Township and Range and quarter section as i am
trying to go to these and trap him.
Also would like to know the distances between the A and B and 0 locations that
were received the same day. Thanks.
Gary
: Re: Becky-project update
Date:Wed, 12 Jan 2000 10:01:30 -0600
From: Gary_Huschle
Becky:
It's unfortunate that we have had bad luck with satellite transmitters this
year. 1940 never broadcast, 1939 is dead 20 miles SE of the refuge, 1938 appears
to have died in late December, and 1936 hasn't given a good location since
November. We have been attempting to find the transmitter of 1939. Cold weather
(-17) and not turning on when predicted have hampered our efforts. We are using
a programmable receiver and will be field-testing a homemade directional
antennae.
Sounds like your students have discovered why we are doing the research on
bitterns. Not much is known and in print about them. The only thing I can add is
the thesis from the two previous graduate students.
Gary
-----Original Message-----
From: Gary_Huschle
Sent: Friday, April 21, 2000 5:59 PM
Subject: Recovered PTT 1939
Soch Lor and I recovered PTT 1939 on April 20. We removed it form the
location at 3:00 pm. The actual location for the PTT since last October where we
found it is:
15U 0303112e 5329548n
or
48 05.326
95 38.642
Should make for some interesting calculations for accuracy of the satellite
locations since October. I have attached some field notes on the process of
finding it.
Gary
(Note: Bittern satellite collar #1939 was placed in August
of 1999 on a bittern at the Agassiz National Wildlife Refuge in northwest
Minnesota)
This message was sent by Gary Huschle - Agassiz Refuge Biologist
Locating PTT 1939
April 20, 2000
PTT 1939 has not moved since late October 1999. Attempts to find the PTT in
December and January were not successful, however, I had narrowed the location
down to an area approximately 50 yards in diameter.
On April 20 the PTT was scheduled to come on at approximately 8:00 am CDT. Soch
Lor and I arrived at 7:30 am and did not pick up a transmission until between
8:20 and 8:30 am. We first tried to use the 401. 6500 directional antennae that
we fabricated according to specifications from Paul Howie, Microwave Telemetry.
We started at one of the Satellite locations for PTT 1939 from last fall that
was a class 3 location. The antenna indicated that the transmitter was to the
south, which was the direction that I had determined last winter. The receiver
had to be adjusted to off frequency to get the directional sensitivity. We
walked over to the sedge/grass area where I thought the PTT should be. Using the
401.6500 antenna we were again able to get directional signal differences with
the receiver tuned to 401.6570 but after more than an hour the directional
information was not consistent and we had not been able to narrow down the
search. In the end the direction that we were pointed to the most with this
antennae turned out to be wrong. We tried using the 164 antennae with the
receiver tuned to the second harmonic 160.6620. We could not pick up any signal.
We then started using the receiver without any antennae and adjusting the
frequency on the receiver up whenever we could were able to receive a signal. We
would then step away about 30 feet in all four directions to see which way the
receiver would still pick up the signal. This took us in the opposite direction
that the directional antennae had led us earlier. We eventually had it boxed
down to what we thought was about a 20 foot square with the receiver set at
401.6580. We decided to try the second harmonic again and while Soch was
changing antennas I set the directional antennae on the ground almost on top of
the PTT and found it laying on top of the grass. The PTT was lying in an
east/west orientation with the antennae pointed to the east and at an upward
angle of about 25 degrees. There were no bird remains present. The transmitter
and bib is in good condition and do not show any tooth marks or fraying. We
tested the second harmonic antennae and it appeared to be very directionally
sensitive and could only pick up the signal from less than 20 feet away.
The G.P.S. recorded the actual location at 15U 0303112 e, 5329548n with an error
of 6 meters. (48 05.326n 95 38.642w)
Locating PTT 1939
April 20, 2000
PTT 1939 has not moved since late October 1999. Attempts to find the PTT in
December and January were not successful, however, I had narrowed the location
down to an area approximately 50 yards in diameter.
On April 20 the PTT was scheduled to come on at approximately 8:00 am CDT. Soch
Lor and I arrived at 7:30 am and did not pick up a transmission until between
8:20 and 8:30 am. We first tried to use the 401. 6500 directional antennae that
we fabricated according to specifications from Paul Howie, Microwave Telemetry.
We started at one of the Satellite locations for PTT 1939 from last fall that
was a class 3 location. The antenna indicated that the transmitter was to the
south, which was the direction that I had determined last winter. The receiver
had to be adjusted to off frequency to get the directional sensitivity. We
walked over to the sedge/grass area where I thought the PTT should be. Using the
401.6500 antenna we were again able to get directional signal differences with
the receiver tuned to 401.6570 but after more than an hour the directional
information was not consistent and we had not been able to narrow down the
search. In the end the direction that we were pointed to the most with this
antennae turned out to be wrong. We tried using the 164 antennae with the
receiver tuned to the second harmonic 160.6620. We could not pick up any signal.
We then started using the receiver without any antennae and adjusting the
frequency on the receiver up whenever we could were able to receive a signal. We
would then step away about 30 feet in all four directions to see which way the
receiver would still pick up the signal. This took us in the opposite direction
that the directional antennae had led us earlier. We eventually had it boxed
down to what we thought was about a 20 foot square with the receiver set at
401.6580. We decided to try the second harmonic again and while Soch was
changing antennas I set the directional antennae on the ground almost on top of
the PTT and found it laying on top of the grass. The PTT was lying in an
east/west orientation with the antennae pointed to the east and at an upward
angle of about 25 degrees. There were no bird remains present. The transmitter
and bib is in good condition and do not show any tooth marks or fraying. We
tested the second harmonic antennae and it appeared to be very directionally
sensitive and could only pick up the signal from less than 20 feet away.
The G.P.S. recorded the actual location at 15U 0303112 e, 5329548n with an error
of 6 meters. (48 05.326n 95 38.642w)
-----Original Message-----
From: Gary_Huschle
Sent: Tuesday, May 09, 2000 4:20 PM
Subject: PTT 1939 Moved to wooded area
On 5/9/00 at 11:00 am the PTT was removed from the water (where we a have not received any transmissions) and was placed in a wooded area.
The location of it now is 48 18.070' latitude and 95
58.929' longitude.
-----Original Message-----
From: Gary_Huschle Sent: Wednesday, May 24, 2000 3:51 PM
Subject: PTT 1939
Jim,
I brought the PTT 1939 that we had in the woods back into
the office at 10:00 am on May 24, 2000. I
need to send it into the company to get a new battery to use it again.
