The Population Structure of the Aruban Whiptail Lizard

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The Population Structure of the

Aruban Whiptail Lizard,

Cnemidophorus arubensis

Lauretta M. Bushar1, Benjamin J. B. Reinert2, Laura M. Y.Reinert2, Quinn W. Reinert2,

and Howard K. Reinert3

1Department of Biology, Arcadia University, Glenside, Pennsylvania 19038

USA

2New Hope Solebury School District, New Hope, Pennsylvania 18938, USA

3Department of Biology, The College of New Jersey, Ewing, New Jersey

08628, USA

The Whiptail Lizard or Kododo

(Cnemidophorus arubensis)

The most abundant of Aruba’s lizards

The Whiptail Lizard or Kododo

(Cnemidophorus arubensis)

The most abundant of Aruba’s lizards

Plays an important role in the island ecosystem

Consumes a variety of plants and some insects

The Whiptail Lizard or Kododo

(Cnemidophorus arubensis)

The most abundant of Aruba’s lizards

Play an important role in the island ecosystem

Consume a variety of plants and some insects

Participates in plant distribution by spreading seeds from

ingested fruits

The Whiptail Lizard or Kododo

(Cnemidophorus arubensis)

The most abundant of Aruba’s lizards

Play an important role in the island ecosystem

Consume a variety of plants and some insects

Participate in plant distribution by spreading seeds from ingested

fruits

Serves as a food source for a variety of predators including the

Cascabel (Crotalus durissus unicolor),

the Burrowing Owl (Athene cunicularia

arubensis) and the Kestrel (Falco

sparverius brevipennis)

In 2006, a lizard population study

was performed in limestone plateau

(baranca) habitat

Purpose: To estimate lizard

population density and to involve

three children, ages 6 though 12, in

an educational experience

A 40 m X 40 m grid was measured

and plotted

25 aluminum Sherman live traps

placed at 10 m intervals and baited

with cheese balls

Traps were checked within 16

hours of baiting

All captured lizards were marked,

weighed, and identified as to

species and sex.

Three species were commonly

seen at the study site:• Kododo or Aruban Whiptail, Cnemidophorus arubensis

Three species were commonly

seen at the study site:• Kododo or Aruban Whiptail, Cnemidophorus arubensis

• Koffie du lechi, Ameiva bifrontata

Three species were commonly

seen at the study site:• Kododo or Aruban Whiptail, Cnemidophorus arubensis

• Koffie du lechi, Ameiva bifrontata

• Waltaca, Anolis lineatus

In our study in 2006, 4 Ameiva

bifrontata and 50 Cnemidophorus

arubensis were caught during a total

of 325 trapping nights No lizards were re-captured

We compare our results to a

study performed in 1994

Year Trap nights Total grid sizeTraps per

hectare

2006 325 0.16 ha 156.25

1994 216 0.96 ha 25

In our study in 2006, we caught

fewer C. arubensis and none were

recaptured

YearCnemidophor

us arubensis

C.

arubensis

recaptured

Ameiva

bifrontata

A.

bifrontata

recaptured

Anolis

lineatus

A. lineatus

recaptured

C.

arubensis

per trap

night

200

650 0 4 0 0 0 0.154

199

497

18

recapture

d;

2

recapture

d three

times

each

5

1

recaptured

three

times

1 0 0.449

The study in 1994 was able to

estimate C. arubensis density from

the recapture data

Year Trap nightsTotal grid

size

Traps per

hectare

C. arubensis per

trap night

C. arubensis per

hectare

2006 325 0.16 ha 156.25 0.154 Not calculated

1994 216 0.96 ha 25 0.449

155

C. arubensis /ha

(CI = 129 to 175

lizards/ha)

Summary In both studies, C. arubensis was the most commonly

trapped lizard

Summary In both studies, C. arubensis was the most commonly

trapped lizard

Fewer C. arubensis were captured per trap night in 2006

compared to 1994

Summary

In both studies, C. arubensis was the most commonly trapped lizard

Fewer C. arubensis were captured per trap night in 2006 compared to 1994.

These differences may be due to

A decrease in C. arubensis density This could be due to predation by the invasive Boa

constrictor which was not known to be on Aruba in 1994

Summary In both studies, C. arubensis was the most commonly

trapped lizard

Fewer C. arubensis were captured per trap night in 2006

compared to 1994.

These differences may be due to

A decrease in C. arubensis density

This could be due to predation by the invasive Boa constrictor which

was not known to be on Aruba in 1994

Differences in trapping strategy

The traps used in 1994 were wooden and had a clear plastic

window at the opposite end, while the traps used in 2006 were

aluminum and had no clear window. Lizards may have been less

likely to enter the aluminum traps

The 2006 study set 25 traps in a 0.16 ha area, while the 1994 study

set 24 traps in a 0.96 ha area.

Different sites were trapped in 2006 and 1994, so there may be

spatial variability in C. arubensis distribution.

Educational experiences

Children learned To identify a variety of

different lizards

To take bearings using a

sighting compass

An understanding of

ecological principles

A greater appreciation of

nature

Educational experiences

Children applied mathematical skills to a real-life problem Making grids

Taking measurements (distance, mass)

Using degrees (when taking a bearing)

Estimating

ACKNOWLEDGEMENTS

C. Baird, K. Dukes, M. Gallagher, and K. Naklicki participated in the 1994 trapping study

Jan Piet Bekker provided the traps used in the 1994 study

We thank the rangers and staff of Arikok National Park

We greatly appreciate the support of the veterinarians and staff of the Aruba Veterinaire Dienst, especially T. J. M. Wools, P. Barendsen and E. R. de Cuba

We would not be working in Aruba without the help and support of R.A. Odum.

Our work on Aruba is performed with the permission of the Department of Agriculture, Husbandry and Fisheries, and we thank T. Damian (Director), P. Portier, and F. Franken for their consistent help in so many ways in making our efforts successful.

We are grateful for the help and support of the late Tom Barmes.

Funding and support for this project was provided by the American Association of Zoological Parks and Aquaria, Coastal Oil Corporation, ESSO Petrolera, S.A., the Toledo Zoological Society, and The College of New Jersey

Holiday Inn, La Cabana Resorts, and MetaCorp generously provided housing.