Spacing Behavior Field Project
The purpose of this lab is to (1) collect data to quantitatively describe spacing patterns
(nearest neighbor analysis), (2) record songs for sound analysis, (3) use playbacks of the
recorded songs to experimentally manipulate behavior and test spacing distances.
This is a two week field project. BRING A FLASHLIGHT!
Week 1. Divide into three groups: flagging, mapping, and recording.
Flagging group: Walk SLOWLY, QUIETLY and CAREFULLY through the study area.
Place a blue stake flag into the ground near every calling male cricket. Place a pink stake
flag into the ground near every female cricket observed. You might see a male cricket
sitting quietly near another male who is calling. If so, flag his location with a pink and
black stake.
Mapping group: Start by making a rough map of the entire study area. After the flagging
group has a head start, measure and write down the distances between neighboring
crickets. That is, for each calling male (big blue flag), write down the distance to his
nearest neighboring calling male (big blue flag). Mark on your map approximately where
the calling males as well as the silent males (pink and black flag) and females (pink flags)
were located.
Recording group: tape record as many calling males as possible, measure the ground
temperature where the cricket was calling and record that on the tape as well. Try to
record at least 5 males each. Be sure to get recordings early and late to increase the
variation in temperature.
The Monday LAB time will be used to calculate nearest-neighbor index and assess
spacing patterns. It will also be used for sound analysis and making stimulus tapes for
week 2.
Week 2. Divide into 5 groups. Each group will have a tape-recorder/player and tape of
cricket song derived from week 1. Each group will playback their recorded cricket song
at 3 distances from each of 3 different crickets (9 playbacks total). The distances to use
are 3 meters, 1 meter and 0.3 meter.
Walking SLOWLY, QUIETLY and CAREFULLY through the study area, approach a
calling male cricket. At 3 meters distance, gently place the tape player near ground level
(but don’t bump it on the ground) with the speaker facing the calling cricket and play the
song for 1 minute. What does the focal cricket do? SLOWLY, QUIETLY and
CAREFULLY move closer, until you are 1 meter away, again play the stimulus tape and
watch for any changes in the males behavior, move forward SLOWLY, QUIETLY and
CAREFULLY and play the song again at 0.3 meter. If the cricket stops calling when you
are moving, remain quiet and motionless until the male starts calling again and has called
for at least one minute. If you get tired of waiting (say around five minutes) you might
want to scrap that individual, and start over (i.e. at 3 meters) with a new one.
Do the 3 playbacks per cricket for more than 3 crickets if you have time and a sufficient
number of crickets are available, but don’t do the same cricket more than once and steer
clear of the other groups and the crickets they are testing or have tested.
IMPORTANT CONSIDERATIONS: Poisonous snakes and Black-widow spiders are
far more likely to be encountered at night than in the day. The area we are using has
fairly closely mowed grass so we can see and avoid problems, but you MUST pay
attention and use a flashlight. DO NOT stick your fingers into crevices or other holes
in the ground thinking that the only thing that could be in there is a cricket!
As always, NO SMOKING and clean up afterwards; no leaving flags around.
Meet at the entrance to Malibu Creek State Park at 7:30 PM
Bring: flashlight, water, small notebook and pens, a watch if possible.
Malibu Creek State Park is about 4 miles up Las Virgenes just past Mulholland Drive.
How to get there:
From CSUN:
Take Reseda to HWY 101 North
Exit Las Virgenes Canyon Road, head south toward Malibu and Pepperdine.
PARKING:
Don’t go into the park, they close the gate, charge for parking etc.
Instead turn right on Mulholland and park in small lot IMMEDIATELY on you left
(about 6 cars might fit here) OR park on Las Virgenes in a large pull-out just before you
get to Mulholland.