Th is dissertation has been microfilmed Mic 60-5331 exactly as received MCMAHAN~ Elizabeth Anne. LABORATORY STUDIES OF CRYFTOTERMES BREVIS (WALKER) (ISOPTERA: KALOTERMITIDAE): WITH SPECIAL REFERENCE TO COLONY j ~ DEVELOPMENT AND BEHAVIOR. )[ ...~ ..~ University of Hawaii~ Ph.D., 1960 .;! /A Zoology ft (~ ~~iversitY ~Cbig~~ ..... Microfilms. Inc.• Ann Arbor. .. i LABORATORY STUDIES OF CRYPTOTERMES BREVIS (WALKER) (ISOPTERA: KALOTERMITIDAE) WITH SPECIAL REFERENCE TO COLONY DEVELOPMENT AND BEHAVIOR A THESIS SUBMITTED '.cO THE GRADUATE SCHOOL OF THE UNIVERSITY OF HAWAII IN PARTIAL FULFILLMENT OF THE REQUIREMENTS FOR THE DEGREE OF DOCTOR OF PHILOSOPHY July 1960 By Elizabeth Anne McMahan ii TABLE OF CONTENTS LIST OF TABLES . ... iv LIST OF ILLUSTRATIONS .. .' ... viii INTRODUCTION ......... 1 STUDIES OF COLONY ESTABLISHMENT AND DEVELOPMENT IN CRYPTOTERMES BREVIS (WALKER) 6 Swarming and Colony Establishment in Nature. 6 Laboratory Studies of Colony Development. 8 Incipient Colonies Established by Primary Reproductives ................ 8 Incipient Colonies Established by Primary Reproductives Paired with Supplementary Reproductives ...... 30 Incipient Colonies Established in Termitaries of Differ ent Kinds of Wood. ......... 33 STUDIES OF CRYPTOTERMES BREVIS BEHAVIOR 51 An Investigation of Feeding Behavior Using a Radio- isotopic Tracer Technique. 51 Plan of Experiments ... 52 Equipment and Apparatus ............ .. 62 Experimental Procedure ............ .69 Reliability of Figures ............. ... 86 Results ..... ..... 'I •••••••••• • 94 iii An Investigation of Termite Behavior Through Direct Observation. .................... .. 164 General Procedure 167 Effect of Molting on Termite Activities 174 Behavior of Individual Termites 182 Time Spent in Food Solicitation. ....... .. 201 Inter-Termite Relationships. ......... .. 203 SUMMARY ... 212 BIBLIOGRAPHY 216 iv LIST OF TABLES Table Number Subj ect Page I Comparison of survival of different primary reproductives from incipient colonies according to age of colony and whether or not self-paired or force-paired. ... 15 II Comparison of number s of eggs and nymphs present in incipient colonies of different ages. ......... .. 21 III Comparison of survival rates and egg and nymph production for the two combinations of reproductives ................ 32 IV Preliminary wood preference tests: Compari­ son by means of weighted scores of amounts of termite feeding on each type of wood. 39 V Comparison of development of colonies from pairs of new dealat.:;s (D-D) in different types of termitary wood. ............ 43 VI Comparison of development of colonies from pairs of supplementary reproductives (5-5) in different types of termitary wood. 44 VII Compa.rison of developme n t of colonies from pairs of old established primary reproduc­ tives (E-E) in different types of termitary wood. ................ 45 VIII Comparison of development of colonies from pairs of new dealate-old established primary r eproductives (D-E) in different types of termitary wood .............. .. 45 v IX Effects of wood preference on colony development 47 X Radioactive termitaries used in feeding experiments ............. 68 XI Pairing schedule for hot and cold termites .. .. 81 XII Errors at the 95 percent confidence level for five- minute counts of representative samples. .. 88 XIII Radioactivity picked up by donor sand recipients in Experiments 1-7............ .. 95 XIV Radioactivity picked up by donors and recipients in Experiment 8. .............. 96 xv Survival of the different termite types from one stage to another. ............ 99 XVI Termite survival according to partner for Experiments 1 to 7 . 102 XVII Mean radioactivity tranFfer percentages for each combination of termite types ........ 109 XVIII Comparison of radioactivity acquired by donor types having access to the same hot termitary (gut volume relationships) " 119 XIX Comparison of radioactivity lost through fecal pellets by isolated and non-isolated termites at various intervals following removal from hot termitaries .............. 130 XX Mean radioactivity transfer percentages for each combination of termite types (omitting sex) after gut corrections and log (x + O. 1) transformation. .............. 141 XXI Transfer percentages of Nand n termites in Experiment 8................ 146 vi XXII Comparison of radioactivity acquired by molted and nonmolted recipients for all types of partnerships. ............... 151 XXIII Comparison of radioactivity acquired during Feeding Period A by molting and nonmolting donors a.ccording to termitary group. .. 155 XXIV Comparison of radioactivity acquired by re­ cipients paired with molted and nonmolted donors for all types of partnerships. ... 159 XXV Activity suspension interval for food solicita- tion, according to instar ........... 176 XXVI Activity suspension interv'al for food donation, according to instar ............ 177 XXVII Activi t y suspension interval for grooming. according to instar ............ 178 XXVIII Activity suspension interval for being groomed, according to instar ........... 179 XXI X Activity suspension interval for gnawing, according to instar .......... 180 XXX Comparison of food solicitation behavior exhibited by the termites of the two colonies observed. ..... .'. ........... 185 XXXI Comparison of food donorship by the termites of the two colonies observed. ....... 186 XXXII Comparison of grooming behavIor exhibited by the termites of the two colonies observed. 187 XXXIII Comparison of frequency of being groomed for the termites of the two colonies observed. 188 XXXI V Comparison of gnawing behavior for the termites of the two colonies observed. ........ 189 vii xxxv Comparison of frequency of jerking behavior during molting and nonmo1ting intervals ....... .. 198 XXXVI Comparison of frequency of egg-tending and pellet-arra.nging for the different termites of the two colonies. ............ 200 XXXVII Comparison of time in seconds spent by each ter- mite in the act of proctodea1 feeding. .... 202 XXXVIII Comparison of frequencies with which each ter­ mite of Colony 1 was observed to solicit food from each of its colony mates. ...... .. 204 XXXIX Comparison of frequencies .with which each termite of Colony 1 was observed to groom each of its colony mates ................ .. 205 XL Comparison of frequencies with which each ter­ mite of Colony 2 was observed to solicit food from each of its colony mates. ...... .. 206 XLI Comparison of frequencies with which each termite of Colony 2 was observed to groom each of its colony mates ................. .. 207 viii LIST OF ILLUSTRATIONS Figure Number Subject Page 1 Cryptotermes brevis (Walker). 3 2 Dismantled termitary of birch tongue blades used in experiments on colony establishment. 12 3 Body length relative to hea.d width for nymphs representing different instars. ...... 27 4 Termitary composed of different types of wood veneer used in preliminary tests of wood preference ............... 35 5 External sex characteristics of G. brevis termites . 60 6 Termitaries used in feeding experiments 65 7 Immobilization chamber for examining termites 73 8 Compa:dson of gain in radioactivity of different types of termites coruined together in hot termitaries for one week. ....... .. 115 9A A comparison of rate of loss of radioactivity by isolated termite types ........... .. 125 9B A comparison of rate of loss of radioactivity by non-isolated termite types ....... .. 126 10 Observation termitary composed of the halves of three birch tongue blades ...... .. 171 11 Comparison of colony activities for the different termites of Colony 1.......... 190 12 Comparison of activity frequencies for the different termites of Colony 2. .... 191 LABORATORY STUDIES OF CRYPTOTERMES BREVIS (WALKER) (ISOPTERA, KALOTERMITIDAE) WITH SPECIAL REFERENCE TO COLONY DEVELOPMENT AND BEHAVIOR INTRODUCTION Cryptotermes, a genus of the family Kalotermitidae, is primarily tropical in distribution. It is represented in the Australian, Papuan, Indomalayan, Ethiopian, Malagasy, and Neotropical zoogeographical regions of the world, ::md it also has one native temperate species in Florida (Emerson, 1955). Probably none of the species is of greater economic importance than Cryptotermes brevis (Walker), the West Indian termite, which is a pest not only in the Caribbean islands, South and Central America, Florida, and Louisiana but also in Hawaii and South Africa. A considerable number of paper s have been devoted to the species, but they have been concerned primarily with direct means of economic control. Life history studies have not been made of ~. brevis, nor has its behavior been closely investigated. The present work was 2 concerned primarily with observations on colony development and with behavior studieA. The work was carried out in Hawaii where C. brevis is an introduced species. It has been unable to invade the native environment but remains confined to human habitations, infesting walls, floors, ceilings, furniture, books, and almost any other type of cellulose product (Zimmerman, 1948). The colonies, which appear not to exceed about 300 individuals, live entirely within galleries formed as a result of feeding on the wood. In­ festation is detectable through the discovery of fecal pellets which the termites push out of the galleries. ~. brevis, like other kalotermitid species, has no true worke::- caste, the work of the colony being done by the nymphal forms of the soldier and reproductive castes. Figure 1 shows alates, a soldier, and two sizes of nymphs of the species. The colony