Methods
In conjunction with the Jornada net primary production studies,
consumer and faunal studies were conducted at or near NPP sites
using pitfall traps. "Consumer plot" trapping grids were
established in 1989 (LTER II) at three creosotebush sites, three
grassland sites, and three mesquite sites, and two tarbush sites
(11 of the 15 NPP sites). Each grid consisted of 4 x 4 rows of
traps spaced at 15 meter intervals. Note that methods changed
somewhat in 1995 at the start of 1995, and separate pitfall traps
for arthropods were also established at this time. Two of the
lizard pitfall grids also moved to different sites at this time.
Very detailed methods that include this change are described in
the attached "dsd" file and others listed under
Additional Files below.
Each trap was 40 cm deep and contained an inner plastic container
and funnel. A ceramic tile was placed over each trap to close the
trap during non-sampling perions. For a 2-week period during each
quarterly sample period, the tiles were raised on one side, and
the traps were checked every 3 days in summer and once a week in
winter. Individual lizards were taken from the traps, identified,
sexed, measured, and weighed. Each lizard was clipped with a
unique number using the codes on the diagram on the field data
sheets. Toe clipping was done from 1989 to 1995. Starting in March
1995 toe clipping was terminated and lizards were instead marked
with a black sharpie marking pen to provide a temporary mark to
determine recapture status over a particular 2-week trapping
period. A black mark was made posterior to the cloaca on the
ventral base of the tail.
Traps were opened for two consecutive weeks every month for the
period 16 June 1989 to 23 August 1991. Beginning after August
1991, traps were opened for two consecutive weeks quarterly: in
February-March (following winter NPP measurements), in May-June
(following spring NPP), in August, and in October-November
(following fall NPP).
Note that arthropods were collected concurrently with this study,
first in the same traps from 1988-1994 (knb-lter-jrn.210008002),
and then in a separate grid of pitfall traps from 1996-2001
(knb-lter-jrn.210008001).
Notes about the data
In 1995, the pitfall grids at the M-RABB, plot C, and G-IBPE plot
A sites were discontinued and new grids were established at nearby
NPP sites M-NORT and G-SUMM. Also included in thes dataset are one
additional site called C-SAND-C that was discontinued early in the
study, and observations from an unknown location (plot values =
NA) possibly associated with M-RABB site. It may be advisable to
remove these observations from analysis.
The species code column (spp) includes a few codes not included in
the original list of lizard species found in 'Lizardcodelist.txt'.
The NONE code signifies that an observation was made at the
pitfall trap, but it was not of a lizard or other species (usually
flooding or other problems). SOSE and BUDE codes probably stand
for Sonora semiannulata (ground snake) and Bufo debilis (green
toad), respectively.
Additional files
'Lizardcodelist.txt' is a text file describing the taxonomic codes
identifyinglizards in the data file (by scientific and common
name). The 'CODE' column should match (at least some of) the
taxonomic codes in the data file.
'lizrdpit.his.txt' is a listing of notes recorded during data
collection. Often they are field notes specific to a particular
record in the data file. The 'pc' column in the data file
references this file when its value is 1.
'lizrdpit.dsd.txt' is a metadata file created during the time of
the study. It contains additional metadata that may not have been
placed into the current EML file for this data package.
'pitfall.pro.txt' is a detailed sampling protocol. It applies to
early arthropod and lizard collections during this project.
'LizardPro.pdf' is another detailed protocol. It was written after
the 1995 changes to the experimental design and is specific to
lizards.
Related publications
none found so far
