Wintering Mountain Plovers in
Texas
Thanks to all the people who contributed data for this
site. As of 3/23/2005 I have posted 283
records from 21 sources
and 87 observers. 266 of the records are Texas records.
For a statewide map:
Click here for a map of Texas
Winter Mountain Plover sightings.
You will see the pre-1965 Oberholser records, accurate only to the
county, shaded in pale green. Other records are very accurrate
at this scale and color coded by date.
For the records:
If you have a GIS software, click
here for a Dbase table with lat-lons to import.
If you do not have GIS software, click
here for an Excel version of the
records.
An explanaton of some of the fields in
the records table:
Source: The source of the record to me.
Observer: Often missing such as in Audubon Christmas Bird Count Records
Poss Acc: This is the possible error in the record's map location,
given in meters.
Lat and Lon: These fields are the NAD83 latitude and longitude in
decimal format.
Count: This is the number of Mountain Plovers reported
ID: This number will be used to label and describe certain records
further in this website
East of about San Angelo, pasture grasses are almost always too tall
for the Mountain plover's preference, so they are found in various
types of cultivated fields, especialy large areas made up of
individually large fields. They usually seek fields that are
relatively barren. The degree of barrenness is reported in the
literature by Kopff, Shakeford and others. These fields are
extremely easy to see on air photos, DOQQs and satellite images.
Landsat images using bands 7,4,2 are excelent for highlighting
plover prone fields. Two examples of how plover sightings fall in
Landsat fields are shown here.
Click here for a Granger
satellite view.
Click here for a New
Braunfels airport area satellite view.
The more red in the satellite image, the more barren the field.
In west Texas where short grass prairies and overgrazed pastures are
often short and barren enough for plovers, the satellite image is a
little more difficult as an indicator but still works
satisfactorily. With this satellite signiature to barrenness it
is possible to trace off in detail Mountain Plover prone areas across
the state. All satellite images used were free from the Synergy
website. DOQQs were also free and from TNRIS website.
Click here for a
satellite and DOQQ derived map of likely Mountain
Plover winter habitat in Texas.
Click here for the
same map but with sightings records shown.
The northward extent of the winter sightings is prominent. Being
insect eating birds, winter severety limits their northward
extent. A comparison of frost free days with sightings does not
fit as well as expected. At first, it looks like there should be
sightings further up into northeast Texas but that area is so forested
there is not much suitable open ground for them
Click here for a superimposed
frost-free days, habitat, and sightings view.
Click Here to go to detailed maps
and specific sighting records.
Summary
The distribution maps seem to be a mixture of both the bird
distribution, and the bird observer distribution. Focused hunting
for the plovers is beginning to take out the bird observer effect.