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64 size classes recorded for females from_Par Pond (Murphy 197?; 1981; Brandt 1989), and Joanen (1969) has reported a positive correlation between body size and reproductive output (clutch size) in this species. Nevertheless, if the reservoir is refilled in the near future and proper nesting habitat is reestablished, a population of large breeding adults should still be present. The emigration of large adult alligators lollowing the drawdown of Par Pond also has important implications for the safety of personnel working in the vicinjty of this reservoir. tsy leaving Par Pond and moving elsewhere in the area, emigaant alligators increase the likelihood that they will come to reside in locations where contacts with site personnel will be more frequent. Just such a situation occurred in the case of the largest male that emigrated from Par Pond in this study (alligator F, Table 2). After resjding in Par Pond for a number of years, this individual left the reservoir and began to frequent the vicinity of a construction site below the retaining dam, where its aggressive actions toward workers at that location required its subsequent capture and "harassment"(through radio transmitter attachment by researchers). This aclion resulted in the animal's moving further downstream out of the conslruclion area, to a point where its contact with site personnel has now been eliminated and yel the animal's movemenl can continue to be monitored/assessed from a safetv Doint of vie\^,. The drawdown of the Par Pond reservoir evidently had little effect on the ability of its remaining resjdent adult alligators to survive the winter months. The winter survival of smaller alligators, particularly very young juveniles, in Ihis population is less certain. 'l'he observations reporled here indicate that at ieast some grorlps of young spent the winter wlth their mothers in subterranean dens although these dens no longer contained water as a resull of the drawdown. Even in the case of the elaborate den reported here holrever, it is not known whether the group of young observed underground in F'ebruary survived for the remainder of the winter months. In any case, female alligators in the Par Pond population appear to be quite adaptable in caring for their nests and young, even under the drastically altered environmental conditions p.oduced by the drawdown. Despite the extraordinary efforls of lemales that tended nesls at Par Pond in the summer of 1991, it is unlikely thal many hatchling alligators from that year survived for long in the lowered reservoir with its almost complete lack of vegetative shoreline cover. Although some halchlings may have been moved by their mothers to other wetlands nearby, there are now probably few if any small alligators still living in the reservoir ilself. Iiurthermore, as the water level continues to be held at its lowered level, habitat conditions in those areas previously used for nesting by the reservoirrs alligators, will remain unsuitable for this purpose in the future, as the result of the loss of extensive stands of shoreline vegetation, This suggests that the reservoir's alligator population will likely experience a second consecutive year ol almost complete breeding failLfe, with still additional years of failure to follow if the reservoir is not refilled. This threat to both present and future reproductive output is probably the most important single source of impact of the Par Pond drawdown upon its resident alljgator population, and if continued through tine, it could have the effect of irsetting backrr this populationrs numbers and age structure to those !vhich characte.ized it in earlier years, as described by Murphy (f9??, 1981). To h,hatever degree this may prove to be the case, the information provided by the long history of previous studjes of these animals should be q vahable assel in interpreting the importance of future changes in this reservoif and ils resident alligator population.
65 ACKNOWLEDGMENTS This work was supported by a contract (DE-AC09-Z6SROO 819) between the University of ceorgia and the United States Department of Energy, and by a subcontract (RR267-015/3436913) with the University of FIorida, Logislic supporl and encou.agement were provided by William D, McCort. Critjcal readings and/or helpful suggestions were contributed by J. Whitfjeld Gibbons, Ronald Chesser, Peter Consolie, Nat Frazer, John J. Mayer, Tony Tucker and F. Ward Whjcker. Irield assistance was provided by Antonio Aponie, Larry Bryan, Mark Dodd, Warren and Walter Stephens, David Unger and Howard Zippler. The extfaordinary 'rspelunkingrr efforts of N. Tod Densmore and Danny L. Stenger were pafticulary important in allovring us to map the underground alligator den vrithout destroying it by digging. Discovery and documentation of the winter-denned female alligator resulted from the determjnation and persistence of Michael Gjbbons, over and above the effofts normajly expected on an underg"aduate field trip in herpetologyl LITERATURB CITED Alcala, A. C. and M. T. Dy-Liacco, 1989. Habitats. b C. A. Ross, ed, Crocodiles and Alligators. colden press pty. Ltd. Silverwater, NSW. Brandt, L. A. 1989. The status and ecology of the American Alligator (Allisator mississipojensis) in Par Pond, Savannah River Site. M.S. Thesis. Florida International University, Miamr. Brandt, L. A, 1991. Long-term changes in a population of Alliqator mississipoiensis in South Carolina. Jour. HerpetoI. 2't4lg-424. Brisbin, I. L., Jr. 1982. Applied ecotogical studies of the American alligator at the Savannah River Ecology Laborstory: an overview of program goals and desigl. In F. W. King, ed, proe. sth Working Meeting of the IUCN/SSC Crocodite Specialist croup. IUCN. cland, Switzerlan,r B.isbin, I. L., Jr., E. A. Standora and M, J. VarRo. 1982. Body temperatlres and behavior of American altigators during cold winter weather. Amer. Midt. Nat- 10?:209-218. Caughley, G. 19?4. Bias in aerjal survey. Jour. Wi1dl Mgt.38:92f-93A. Chabreck, R. H. 1963. Methods of capturing, marking and sexing altigators. Proc. Ann. Conf. S.B. Assoc. Game and Fish Comm. l?:4?-S0. Chabreck, R. H. 1966. The movements of aliigators in Louisiana. proc. Ann. Conf. S.E. Assoc. came and Fish Comm. t9:102-110. Chen, 8., W. Chaolin and L. Baodang. 1990. Observation on the bu[ow of Chinese alligator. IO Proc. l0th Working Meeting of the IUCN/SSC Crocodile Specjalist croup (Vol. 1). IUCN. cland, Switzerland.
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CROCODILES Proc€€dings of the l
Page 3:
FOREWORD The two volumes of this PR
Page 6 and 7:
Elsey, R M, McNease, L & Joanen, T:
Page 9 and 10:
CFAZ CIIAIRMAN'S OPENING COMMENTS F
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PRESENTATION FROM THE MINISTER OF E
Page 13 and 14:
Fitting Curves to crocodilian Aqe-s
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7 a.set of uniforrn random nunbers.
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2. VON BERTAI"ANFFY MODEL FOR GROWT
Page 19 and 20: 11 The -following four tables give
Page 21 and 22: UNIFoRU sarnpling MEDfUM sahpl ing
Page 23 and 24: 15 Sectior IV: Actual Croc Data, l,
Page 25 and 26: 1'l (ii) Linear regressron. same ra
Page 27 and 28: 1,9 rejecting nufl hypotheses that
Page 29 and 30: 21 Brisbin, I.L., Jr., c.c. White,
Page 31 and 32: Iength lthich corresponds to the ni
Page 33 and 34: 25 Because of lack of funds Eo carr
Page 35 and 36: 27 Despite the fact that during a p
Page 37 and 38: 29 FIGURE N9 2 BLACK CAIIIAN POPULA
Page 39 and 40: I'Effect of diets conplenented vith
Page 41 and 42: 3i Two of the 6 x 2 m. tanks four e
Page 43 and 44: : .i ; -3, E .-1 t FFdF !_9 + + + +
Page 45 and 46: 10 Table IV : fl aernathological Re
Page 47 and 48: 4l 4.- CONCLUSIoNS 1) The most favo
Page 49 and 50: 43 THE INVOLVEMENT OF RURAL COMMUNI
Page 51 and 52: 45 the rainy season and, in conhast
Page 53 and 54: 47 difficulties and the isolation o
Page 55 and 56: 49 Eacb time that one of the villag
Page 57 and 58: 51 CONCLUSION Naturally, these rcsu
Page 59 and 60: 53 LONG-TERM POPUT-A.TION S'ruDIES
Page 61 and 62: 55 'Ile study reporled here was des
Page 63 and 64: 5'7 made of transmilteFequjpped ndm
Page 65 and 66: 59 wilhin the reservoir was lypific
Page 67 and 68: 6l However the use of such winter d
Page 69: 6.1 surface to breathe (Kellogg 192
Page 73 and 74: Murphy, T. M., P. M. Wilkinson, J-
Page 75 and 76: 69 t 3 ^ 3 :9s 3P o ;x !B 'rr.l9 3e
Page 77 and 78: 7l FoDd B + i Poud C I Pltllr. l. U
Page 79 and 80: 73 9 October 1991 L t' I L t' 26 Ma
Page 81 and 82: 75 80 -r- 1987-88 + 1991-92 t -40 .
Page 83 and 84: 77 GROWTH RAIE OF CAIMAN (Caiman cr
Page 85 and 86: 79 Values of the life lable paramet
Page 87 and 88: 81 REFERENCES Craig. G.C., D. Si.C.
Page 89 and 90: 83 CUMATIC F{w L Stirldi .6.aiDS EF
Page 91 and 92: 85 2. Behavioral facilitation of re
Page 93 and 94: 87 TeEperature, hy&ic coaditionq aa
Page 95 and 96: 89 The sexual behaviors of irdividu
Page 97 and 98: 9l 2o I E F conuor o.r r.0 r0.0 a0.
Page 99 and 100: 93 Referetrces Ber!, H.A. (1990). T
Page 101 and 102: 95 GROWTH RATES AND BODY CONDITION
Page 103 and 104: 97 LIPID AND FATTY ACID COMPOSMONAL
Page 105 and 106: 99 be removed sustalnably, provided
Page 107 and 108: 101 necessary as the endurance of t
Page 109 and 110: 103 Table 2. The ratio of first sig
Page 111 and 112: 105 3) Movement and dispersal The r
Page 113 and 114: 107 Disease Trend$ on Crocodite Far
Page 115 and 116: 109 Fuigol and other dermar,?ir - d
Page 117 and 118: 111 THE FEEDINC ECOLOGY OF TWO NILE
Page 119 and 120: 113 areas outside the National park
Page 121 and 122:
115 been done for a tlpical populat
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117 ACKNOWLU)GEMENTS This study was
Page 125 and 126:
119 THE STATUS AN'D DISTRIBUTION OF
Page 127 and 128:
Figure l: Crocodile Survey - Tanzan
Page 129 and 130:
123 :rD ES e € a 69 PE e 3 Er t !
Page 131 and 132:
125 Ruaha River (Figure 2) The Ruah
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127 lake Mtera (Figure 4) This is a
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t29 with 6shermenand subsistence f'
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lil Kilimmjaro/Tanga Region Pa gani
Page 139 and 140:
133 The numbers of crccodiles durin
Page 141 and 142:
135 REFERENCES Chabreck, R.H. 1966.
Page 143 and 144:
l -37' 3.1.4 lagal Trad.e Local tra
Page 145 and 146:
l.l9 In order to gecure credibility
Page 147 and 148:
l4l 'rould apply to 6kins of good h
Page 149 and 150:
143 This infdrrDation cduld be supp
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l.l-s ].nternational reEplfnstbitit
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t4'/ illegal sttjns in their pr,r,d
Page 155 and 156:
149 CROCODILE SKIN INDUSTRY IN ETII
Page 157 and 158:
l5l Table 2. Ouotas for Ethiopian c
Page 159 and 160:
153 depriving EWCO of incentive for
Page 161 and 162:
155 A PRELII{] NARY ASStsSS!.IENT O
Page 163 and 164:
15',7 Origin l Payert lltosk Breedi
Page 165 and 166:
159 dropped, producing 23 and l9 eg
Page 167 and 168:
l6l This figure ts even lorrer than
Page 169 and 170:
163 =z 3F \riciNoraj {
Page 171 and 172:
165 References EArr,ER, R.D. ( 1976
Page 173 and 174:
t6'1 IPPIIDIX tt BtoBtE cI0@(DILX n
Page 175 and 176:
l()t/ Backqround l,lelano5uchus nio
Page 177:
t7l The numbers of black cainan c'b
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