Perch Dissection Lab

By:Arlenn Maldonado P.7 Guzman PAP Biology

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Circulatory system

The circulatory system of a Yellow Perch is a low pressure, single loop system. This means that there is one direction of blood flow from the heart, which acts as a pump. Deoxygenated blood is pumped throughout the heart and goes onward to the gills. This is where the blood becomes oxygenated (the gills), getting rid of carbon dioxide. From here the blood goes straight to the body. This makes up one single circuit of the blood flow: Blood pumped à Oxygenated à distributed throughout the body à returns to heart. Blood pumped from the heart in this type of circulation is purely deoxygenated.

Information you NEED to know!!!!!

Ge­o­graphic Range

Yel­low perch, Perca flavescens, are north tem­per­ate fish. They ex­tend from west cen­tral Canada and the Hud­son Bay area east to New Brunswick, down to South Car­olina and west to Kansas (Clay 1975; Her­man et al 1959).


Yel­low perch are found mainly in lakes and some­times in im­pound­ments of larger rivers. Clear water is im­por­tant as ex­ces­sive tur­bid­ity and silt could lead to death of perch. Perch do how­ever have a high tol­er­ance for low oxy­gen con­di­tions. They in­habit water of mod­er­ate tem­per­a­ture, avoid­ing cold deep water and warm sur­face wa­ters dur­ing the sum­mer. Young perch gen­er­ally in­habit shal­lower water than larger ones, though as tem­per­a­ture in­creases all move to cooler, deeper water (Walden 1964; Her­man et al 1959).

Phys­i­cal De­scrip­tion

Adult yel­low perch are usu­ally golden yel­low; young are usu­ally more whitish. There are 6 -- 8 dark ver­ti­cal bars on the sides of these fish. Their eyes are green to yel­low. They have a spiny dor­sal fin with 12 -- 14 spines and a sec­ond dor­sal fin with 12-13 soft rays plus 2-3 spines (Craig 1987; Her­man et al 1950). There is usu­ally a black­ish blotch on the mem­brane be­tween the last 3 or 4 dor­sal spines. Their anal fin has 2 spines and 7-8 soft rays. The lower fins of adults are usu­ally tinged yel­low or red; this is es­pe­cially no­tice­able on males dur­ing breed­ing sea­son.


Fe­male yel­low perch ma­ture at ages two to four, males usu­ally ma­ture one year ear­lier. Spawn­ing takes place in the spring (April through early May) when the water tem­per­a­ture reaches 45 - 52°F (Craig 1987; Her­man 1959). The av­er­age num­ber of eggs laid per fe­male is 23,000. After de­po­si­tion the eggs rapidly swell and harden. Eggs hatch in 8 -10 days and the emerg­ing the fish are 4 - 7 mm in length.

Yel­low perch lar­vae have large mouths, well-de­vel­oped jaws, teeth and eyes. They begin ac­tive feed­ing at 7.0 mm but still ab­sorb food from the yolk sac. At 21- 27 mm the fins are fully de­vel­oped with spines and rays. The fish be­come fully scaled at 36-37 mm. After hatch­ing, the lar­vae first ap­pear nearshore and then be­come pelagic (move off­shore) and re­main so until their fins fully de­velop (Craig 1987; Fis­cher and Willis 1997; Walden 1964). Yel­low perch are rel­a­tively short-lived fish, few over seven years old are ever caught (Her­man et al 1959).


Yel­low perch are rel­a­tively poor swim­mers; they do not ac­cel­er­ate quickly. Yel­low perch are school­ing fish which may help over­come this poor swim­ming abil­ity by pro­vid­ing pro­tec­tion for younger fish and eas­ier prey cap­ture for older fish (Craig 1987). Young of the year perch tend to school more than older fish, which oc­ca­sion­ally travel alone (Helf­man 1979; Her­man et al 1959). The schools are spin­dle shaped and con­tain 50 -200 fish that seem to be arranged by size and age (Her­man et al 1959). Fe­males and males are often in sep­a­rate schools (Craig 1987).

Vi­sion is nec­es­sary for school­ing, and perch in most stud­ies are shown to break up in the evening and re­form in the morn­ing (Helf­man 1979; Her­gen­rader and Hasler 1968). Light lev­els may be im­por­tant de­ter­mi­nants of yel­low perch ac­tiv­ity. They are ac­tive dur­ing the day and in­ac­tive at night (Helf­man 1979;Craig 1987). Over­all, yel­low perch do not travel far through­out the year.

Perch are an im­por­tant food source for top preda­tors such as the wall­eye, north­ern pike, muskel­lunge, and in colder wa­ters lake trout. Her­ring gulls and div­ing ducks also eat them (Her­man et al 1959). Pump­kin­seeds and white suck­ers ap­pear to com­pete for the same prey re­sources as yel­low perch (Craig 1987; Heath and Roff 1996). Stom­ach con­tents of small wall­eye often con­tain young yel­low perch. In Lake Erie it was es­ti­mated that at least 18 % of po­ten­tial 18-mm yel­low perch were eaten by walleyes in 1988. White bass and white perch added to this per­cent­age (Hart­man and Mar­graf 1993).

Food Habits

Young of the year yel­low perch feed on zoo­plank­ton, then as they grow they switch to ben­thic macroin­ver­te­brates and fi­nally fish (Gerk­ing 1994). In Lake Erie and other lakes, young of the year switch from mainly zoo­plank­ton to ben­thos dur­ing mid­sum­mer de­clines in zoo­plank­ton bio­mass (Post and Mc­Queen 1994; Rose­man 1996).

Yel­low perch have small back­ward slant­ing teeth lin­ing the jaws and gill rak­ers that strain out small pelagic food sources from the water (Her­man et al 1959). Their mouth is sub­ter­mi­nal which makes it easy for them to feed at the bot­tom (Par­rish and Mar­graf 1990). Yel­low perch swal­low their food whole (Weath­erly 1972). They switch to prey longer than 1.7 mm when they reach total lengths of 60 - 75 mm (Schneberger 1991). In large fish, the net en­ergy gained by eat­ing large prey, such as ben­thos and fish, out­weighs the dis­ad­van­tages of cap­ture and di­ges­tion (Mills et al 1989).

Eco­nomic Im­por­tance for Hu­mans: Pos­i­tive

Yel­low perch are eco­nom­i­cally im­por­tant in terms of a food source and recre­ation. Yel­low perch sup­port a com­mer­cial fish­ery in Lake Michi­gan, Lake Erie, and Lake Huron. The peak com­mer­cial catch of yel­low perch in Lake Erie was 13,546 tones in 1969. The 1980 - 1984 Cana­dian yel­low perch com­mer­cial catch rep­re­sented 55% of the value of all fish landed in Lake Erie by Canada (Craig 1987; GLFC 1997; Jude and Leach ). Yel­low perch are also a very pop­u­lar sport fish that con­tributes lots of tourism and recre­ation dol­lars to the econ­omy. About 85% of the sport fish caught in Lake Michi­gan are yel­low perch (Fran­cis et al 1996). Sport an­glers' catch in Lake Erie in 1984 was 58 times larger than the com­mer­cial catch (Ruet­ter and Hart­man 1988).

Eco­nomic Im­por­tance for Hu­mans: Neg­a­tive


Iwill be learning about the external and internal anatomy of a lamprey. I will focus on the organs, structures, and functions of the digestive system. I will also understand the ecological role of the lamprey.