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Discussion"
'Ite cons€rvatior of endargered o! threatered spccie's of reptiles is a press.in-g problem One
imDortant facror is lhe sex ratio oi the breeding populaion (t!e secondary sex ratio) wtich is strongly
;ii;;;;";;Jo
at binh (rbc prioar! J ratio) rSD thus has profound{onsequenc€'s for
;;;;r;;;. iut l* ui* .o.t .r"-ty rlemorstrated in sea turtle hatchery-programs that
are feared to Lvl produced mostly malc tu4leE reducilg lhc co$ervation benehts oI tbese proglam'
- - -
Maov c"ocoiiliaa progams-involw naaiir:latioo ;f eggE eiLber fton captivetreeding or ftom
.*"d;;;;;,,b" is,i'ios ton *hi.n a''e released b;d( to tbe wild' coltrol of the sex ratio or
'cap-tiue
ii;EJtt;"",v.
u.".atg p'ogra-s for scverlv esdans{red sPecies cir arso
ffii?5.t" *'"ii t"",,tat'oo or 'ati-oi i"i'cea;"g stocl to opli'is€ botb p'oducrioD and
"ex
g"rJ-U" a*-t"r,y.i*p*e-poputatioos for future tedocldrg iD the wild Tbete are also Practical
6"r"Ot" ," -tiptf.d"g si ratios. ooe s"x o. th" other may grow-faster or b€ norc anealable to
caouve conditio$. Wterc sustainable use progams are bcilg us€d as an rDc€nolE ror urc
tr'ose.vatioo of wiLl p"pulations the efiiciercy of producdon for cooEcroal use is aD inportant
comooneut ***ri" of econonic viability arrd succ€ss.
".r" """rr"ui" i"UJa o"tit ro. -*ipulatisg sex ratios i-o c'ptive breediag groups has
"o*
b*" t;;t;i tht;;perature of incubatiott. Wtile this is a proven eflectire nethod practical
coDstairts lmit its applicability. Ir lemote ateas tec-hnicd support, equrP-Eent aDd rclraDle power
.uooru -" .ii ,eropeiaturc naaipularioo facilities n;t fan witr disasterous coosequenc€s for
;;";;";;;; "".t"" ii! i."t"iqu" or'"pottl's esss with h;rEoDqs to i'duce desired sex of
.tbe
offsorios oro;id"; ao e*y anrl iaexpeosirc nethod- -i'hc proct'durc bas no nortality associatcd with its
aooicadoo -d ha" been demoDstratcd oD a s/ide variety of reptilian species Tbe reproductve
.ii*:" l-"t .t. ;ritJ offspriag appears to be nornat ir tlc several speries tesled and tte
-l*,r""rc "i oi t-u*" on pti"s is oft";"Lr"*i. Thc p'ocldure for conducting tlis proce'ss has a
iu-,eolo"-iair* *i* rl" iigfiassigned to a non-ptofit organization (Reptile Cocen-alion Intemational
il;;ilil. t!";'*-.ation-of reptites a.orl any iacomc derived fron the procedure will be used to
support fiuther researci add dcvclopment.
We have de'scribed how the sodal cDdrotseht car detemiDe tho level of reproduction in
caDtiveDoDulaliols.ltisalsoclearthatelvionmcntalvariableshaveeffectsonthedevelopmedof
Jur".i*iiJ *" ras, it to adulthood. Tbus, maintainarc of captive poPulatio!3 of e aryered (or
even acincr in the wild) reptiles should be nindful of thase factors'
i -
th" d"u"lop-"ot oi ar effectirt mettod to treat developing eggs-.loPicalyrvith hormones allo*s
sex determinatioaio be manipulated in