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Peregrine
Summary:
Students create a food chain for the Falcon Food
Peregrine Falcon that includes the effects
of a pesticide (DDT) on the food chain. Chain
Learning Objective:
Students will:
1. place the Peregrine Falcon in a food uminsi
chain. Activity 8 ichard
2. turn the Peregrine Falcon food chain Photo:
into a food pyramid.
. learn how pesticides such as DDT
aterials: Student copies of Peregrine Falcon
uild up (ioaccumulate) in the Peregrine Fact Sheet student copies of Peregrine Falcon
Falcon food pyramid. Food Pyramid orsheet and a red marer or
pencil crayon for each student
. consider how to preent maing ocation: ndoors
mistaes similar to the one that almost
caused the e tinction of the Peregrine Time reuired: 2 classes
Falcon.
Background Information:
The Peregrine Falcon has always been a rare species in New Brunswick. urriculum
Before 1 scientists belieed that there were only a handful of pairs inks:
nesting mainly along the Fundy coast in summer and migrating to the southern
and entral and outh merica in winter. uring the mid 1’s this maestic bird lassify organisms
of prey all but disappeared from the
aritime Proinces and other areas of North according to their
merica. The cause was T a pesticide used widely throughout North merica in role in a food chain
both the nesting and wintering grounds of this species. or web and draw a
diagram to illustrate
Pesticides including herbicides fungicides and insecticides are made to control the food chain.
certain organisms. erbicides control unwanted weeds fungicides kill unwanted lassify organisms
fungi and insecticides control pest insects. hen these substances contain according to their
chemicals that do not break down easily they eentually build up or accumulate in role in a food chain
nature. Pesticides can build up in a water or food source used by wild animals and or web and draw a
humans. The full effects of a pesticide such as T are only realied after many diagram to illustrate
years of use. the food chain.
In New Brunswick and in many other places where Peregines were found T
was used throughout the 1’s and ’s to kill the spruce budworm and other
pests. hemicals such as T traelled up the food chain through insects to their
predators eentually reaching top predators like the Peregrine Falcon. The higher
up in the food chain an animal is the greater the amount of pesticides that will
build up in its tissues. s a result concentrated toins were ingested by the
Peregrine Falcon with each pesticidecontaminated meal.
The use of the pesticide T didn’t kill the Peregrine Falcon directly but affected
the Falcon’s ability to reproduce. ometimes it preented the female from laying
eggs. ometimes it caused such thin shells in the eggs that they broke under the
mother’s weight in the nest incubation.
In the late 1s and early 1s use of T was either banned or restricted
across North merica. This ban together with captie breeding and release
programs reestablished Peregrine Falcon populations. Birds were obtained from
falconers raised in a central facility in ainwright lberta and shipped to areas
where they had disappeared. fter seeral years of carefully rearing and releasing
birds the species has come back in NB and other areas in eastern North merica.
This is one of the most successful recoery stories for speciesatrisk.
T is still a threat to the Peregrine Falcon since it continues to be used in some
entral and outh merican countries where Peregrines spend the winter. T
affects Peregrines that migrate to areas where it is still used. ther pesticides
currently in use may also pose a threat to birds of prey such as the Peregrine
Falcon.
ctiity:
1. plain the background information to the class. ae students read their
copies of the Peregrine Falcon fact sheet.
. eiew the concept of a food chain. food chain is the pathway of energy
and food through an ecosystem that begins with plants and ends with
carniores. It shows who eats whom.
. Proide a sample food chain such as cloer plants rabbits fo. laborate
on the eplanation to turn it into a food pyramid. food pyramid is a diagram
that shows the passing of energy from one organism to the other with the
energy always moing upward. food pyramid is a good isual way of
understanding the concepts behind a food chain. plain the illustrated
eample of the food chain and pyramid.
In this eample energy is transferred upward through three leels of
the food pyramid: from the sun to the cloer plants from the cloer
plants to the rabbits and from the rabbits to the fo.
. istribute the Peregrine Falcon Food Pyramid orksheet.
tudents will begin by making a food chain using the following organisms:
plants insects smaller birds and Peregrine Falcon.
. sing the Peregrine Falcon Food Pyramid orksheet hae students start at
the top of the pyramid and work their way down. sk students to estimate
the amount each species might eat on a gien day. For eample how many
insects would a small bird eat each day hateer amount students select
should be drawn in as indiidual species in their food pyramids. There is no
eact answer but students can be reminded to be as realistic as possible.
Peregrines feed on small birds contaminated with T
mall birds feed on insects contaminated with T£
Insects feed on trees contaminated with T£
Trees and plants in forests or agricultural fields are
sprayed with the pesticide T£
ake sure that students draw each of the species they estimate at each leel of the food
pyramid as well as lines showing meals for eample which birds ate which insects.
. sk the students to identify each leel as consumer producer and decomposers.
Optional Activities:
. eiew the concepts of bioaccumulation and T. Bioaccumulation is the
concentrating of substances, like DDT, in the food chain. It results from organisms
repeatedly eating other organisms that contain amounts of the toxin. The higher
up in the food pyramid that a species is, the greater the concentration of toxins.
. sing the Peregrine Falcon Food Pyramid orksheet and the species already illustrated
at each leel students will learn how T affected Peregrine Falcons. Tell students to
assume that 1 of all the plants in their pyramid contained one unit of T. ircle the
T affected plant species in red.
. Following the lines already drawn by students connect the insects to the plants and circle
any T affected insects. If any insect ate more than one T affected plant two or more
units of T can be represented by drawing red circles net to the insect.
1. For the small birds follow the lines connecting them to their prey insects. how multiple
units of T in small birds by drawing red circles net to the birds.
11. Then calculate the total units of T that hae accumulated in the Peregrine Falcon by
counting the red circles.
Discussion
• sk students how many units of T they think the Peregrine Falcon can handle
without showing the negatie effects of this accumulation.
• sk students what happened when there was a large number of each species in the
food chain hat happened when there was a small number of species in the food
chain
• hy doesn’t the T disappear as energy is transferred from one species to the other
in the food pyramid
• eiew the term “bioaccumulation”. ow does bioaccumulation affect the Peregrine
Falcon
• hat else might bioaccumulate in the Peregrine food chain
ariations:
1. onsider what would happen if there was one less or one more leel in the Peregrine
Falcon food pyramid.
Peregrine Falcon Food Pyramid
Worksheet
tudent Name: ¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤
A. Food chain
ake a food chain and put the following organisms in their correct place within the chain:
plants Peregrine Falcon small birds and insects
¤¤¤¤¤¤¤¤¤¤¤¤¤¤ ¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤ ¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤ ¤¤¤¤¤¤¤¤¤¤¤¤¤
B. Food pyramid
se the species in the food chain to make a food pyramid starting at the top. alculate
the numbers of species that each would eat working down the pyramid.
ake sure that
there is only one indiidual at the top of the pyramid.
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