Question

When sea urchins were introduced to an intertidal zone in Pacific Beach, California, only three of 15 were alive one year later. La Jolla, California has its own intertidal zone that is almost identical to the intertidal zone in Pacific Beach. Ignoring the effects of carrying capacity, how many sea urchins would need to be introduced into the intertidal zone of La Jolla in order to have 12 remaining at the end of one year? Show all work

Continuing the experiment, 42 sea urchins are already present in the intertidal zone of La Jolla when the scientist conducting research arrives. These animals were brought to La Jolla by a biologist one year earlier. Ignoring the effects of carrying capacity, how many sea urchins were originally brought to La Jolla? Show all work. (4 points)

Answer 1

Consideving given cendithion noing Caning cecib ebbeck, identicel intertidal Bone year (3s) sO-2 ber year 1e.CNJ4H) 3 alive out 6 one need to inboduee i-e (12 X5) 60 sea urchin In Lajol|a l42/60) 02year to remain 12 at the end 63 year, S0, / 5 times mCre -1 whtch atve grooth a year i-e Given 42 Sea urchm presemt at the end pear, hen e (b tnpoduced other 210 sea urchin ohch give growth te pear e 7o)-(4/21) UTchin cUere Sea 5 timer Screm tst 42x5) -e one peas esr lie 4 02 year