PHILIPPINES

The goal of the project is to reduce vertebrate damage to agricultural
crops in the Philippines and other Southeast Asian countries. Dr.
Russell F. Reidinger, Jr. (January-August) and Mr. Lynwood A. Fiedler
(November-December), representing the DWRC, nine Filipino biologists,
and a number of graduate students and cooperating personnel worked
toward attainment of this goal through developmental and adaptive
research projects, training programs, and extension activities.

Research projects during 1978 involved investigations aimed at
reducing vertebrate pest damage to rice, coconut, corn, and sugarcane
crops. Emphasis was placed on: development of delivery systems,
including bait station comparisons and evaluation of various bait for-
mulations; damage assessment and yield loss determinations; evaluation
of traditional farm level control technology; behavioral studies; and
development of a rodenticide resistance monitoring program. Training
continued to be a major part of the program both at the individual and
group level.

These activities are summarized below. Many of the studies were con-
ducted by graduate students as partial fulfillment of their degree
requirements (acknowledged in parentheses). In several cases, the
reports are partially repetitious since the work was initiated prior
to 1978 and has been discussed in previous (1976 or 1977) annual
reports.

Behavior of rats in relation to coconut damage

Rat damage is a common problem in coconut plantations and is a special
concern in the Philippines, the world's leading exporter of copra.
This study was aimed at developing a better understanding of the rela-
tionship between rat behavior and coconut production.

Field data were collected near Calauan, Laguna, in six 1-ha study
plots within a 120-ha coconut plantation with a history of chronic rat
damage. Trapping was used as a representative control method in two
plots (treatment), it was simulated in two plots (reference), and
radio telemetry was used in the remaining two plots to study rat move-
ment patterns. Feeding preference studies were conducted in labora-
tory cages. Damage and harvest data were recorded in both treatment
and reference plots and rat activity was monitored in both with
tracking tiles. Biological data were collected from rats trapped in
both treatment and reference plots during the final trapping period.

Rattus rattus mindanensis, R. exulans, and Suncus murinus were common
at ground level. R. r. mindanensis and R. exulans were also trapped