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he corrected or that geneticalh im- <br />proyed procedures can cure all major <br />hatchery faults.:1nv panacea-grasping <br />is fallacious, and applying principles of <br />population genetics, necessary as it is, <br />++•on't remedy all the adverse ~ waits of <br />hatchery fish. (;enetic reforms can't <br />eliminate certain anatomical, physi- <br />ological, and heha~ioral damage ac- <br />quired in hatchery life. The aberrant <br />behaviors that fish learn there may he <br />especially detrimental. Most +eill prob- <br />ably be hard to remedy; some ++ill he <br />unavoidable. \-Iavhe that's why fish be- <br />ha~ior is still largeh• neglected in hatch- <br />ery reform. <br />THE MADDING CROWD <br />Bccausc• {islt hatchetiesarephysicall~ <br />and biok>gicalk sounlike nauu-al water <br />bodies, especially streams, hatchery fish <br />don't learn to use tnany nann•al tea- <br />turesthat would benefit them and don't <br />learn to avoid or contend with certain <br />adversities of life in the wild. In the <br />pre+ious issue of'Trrntt, l discussed prob- <br />lems ofnot learning to use stream fea- <br />ntres for coyer, optimal feeding and <br />resting sites, predator avoidance, and <br />so on. <br />I also mentioned there that the ex- <br />lreme cr-au+din,~T to which hatchery fish <br />are subjected may be a major cause of <br />unnatural beha~irn-.Ofthe unfavotahle <br />factors in hatchery life, this ntav he the <br />hardest to change , fir super{ ontentra- <br />lion of fish is a primary hatchery char- <br />acteristic. <br />.~ hatchery is essentially a feed lot. <br />Feed-lot animals, especialh~ if kept there <br />from birth to adolescence, arc: not likely <br />to do well +vhen released outside their <br />artificial home. V1'tten "freed," then must <br />feel insecure (to say the least). They <br />Wray }~ terrified. r1s the few snrdies on <br />the subject show, they unclcrgo stress <br />and undertake all sorts of nervous, inef- <br />fective acti+it`. <br />A small step toward reduced crowd- <br />ing isplanned inone proposed project, <br />a huge, controversial system of salmon <br />and steelhead hatcheries for the Sakima <br />River, a uibutan• to the Columbia in <br />Washington State. (Conser~ationistsad- <br />vocate restoring the much-abused river <br />system by "re-++•atering"parts now deg+'a- <br />tered In agriculuu-e and 1>y otherwise <br />mending poor habitat rather than <br />pumping hatchery fish into it, but pow- <br />erful interests, while doing little to ad- <br />just harmful human activities, arc: <br />forging ahead with hatchery plans. Be- <br />cause hatcheries have a bad name, they <br />are careful to call theta "production <br />facilities." Also to make things sound <br />atU active, they portray the project as an <br />"experiment," as was done long ago <br />with the Leavem+-orth hatchery.) In ac- <br />knowledging drecrowding problem, the <br />aquaculturists plan to reduce normal <br />"loading densities" of race~+•av ponds by <br />half-. <br />Let's look at what cutting hatcher}~ <br />fish density by half may mean. I've been <br />told the normal densitcof s<tlmonids in <br />hatchery U-oughs and raceways is =lIX7 ro <br />60~I karre_s the density of natural popula <br />lions in good streams. To check this, I <br />consulted biologists trained in hatch- <br />erymethods and did some calculations, <br />using literaurre figures on the amcen- <br />trttions of voungwild U-out-and to he <br />conservatiyc, using data apphing nnh~ tv <br />pm'linns c f streams that are the l~r•ritories of <br />small (hatcher}•-sizedj trout, not the <br />whole stream volume towhich they have <br />access. In terms of stream vohune (wet- <br />ted space) occupied, I found a nnu•h <br />lower figure: Trout were "only" `L00 to <br />250 times more closely packed in hatch- <br />eries than in nauual stream territories. <br />However, loading densities in hatch- <br />eries are based on weight of lisp per <br />amountof u~aler~lure~ (pounds of fish per <br />gallon per minute} in the container. <br />()n this basis, loading density in hatch- <br />eries may indeed be around 4O0 to 6(?0 <br />times that of natural streams because <br />the average trout sU•eam's portion that <br />trout occupy, probably has several times <br />the flow of a typical raceway (and the <br />entire stream has much more yet). <br />Therefin•c , the proposed "loading" <br />in the lakima hatchery project, even <br />though only half of the hatchery norm, <br />arty still he a itunclrecl times t}te natural <br />nrn-m in terms of weight per wetted <br />volume and 200 la 300 times greater <br />than natural in terms of flow. <br />Imagine anormal-sized home f<~r a <br />funih of four people. Then imagine <br />doubling that nurnher of people, w•ith- <br />outexpanding the house. And imagine <br />not allowing them r~t~erto venture out or <br />have contact with the outside +vorld, <br />other than having food and medicines <br />shoved at them, until they are abrupth• <br />and permanenth' ejected after a fey+- <br />years. Might those people feel crowded' <br />~~lould they, when "released," have be- <br />ha+iors that fit in ~+ith normal human <br />socien~ <br />Vow imagine increasing the house- <br />hold concentrttion to prison-like or <br />worse conditions of 100, 200 or 3fH} <br />times normal instead of only doubling <br />it. ~47tat would chat do to people' Artd <br />what can we expect to happen to trout <br />and salmon when r wised from Matching <br />to adolescence tinder such circum- <br />S[anCeS.' <br />"I'KOI~T AUTUMN 1y92 <br />