5.0 AQUATIC & MOSQUITO EXAM
QUESTIONS AND ANSWERS GRADED A+
2025/2026
List the roles plants play in a healthy aquatic ecosystem. - ANS -producing oxygen
-preventing shoreline erosion
-lessening excess nutrients during growing season
-stabilizing lake bottom
-providing food and habitat for fish, waterfowl, and other aquatic animals
List ways that excessive plant growth can adversely affect the ecology and uses of a water body.
- ANS -harm ecology of aquatic ecosystem
-curtail or prevent recreational water uses (e.g. fishing, boating, swimming)
-impart tastes or odors to drinking water
-hamper water treatment operations
-adversely affect aesthetics, resort trade, and waterfront property values
-produce toxins that harm animals drinking the water
Describe the general growth habits of, means of dispersal and potential problems caused by:
Emergent aquatic plants - ANS -*growth habits*: rooted in shallow water, most growth above
water
1 @COPYRIGHT 2025/2026 ALLRIGHTS RESERVED.
,-*means of dispersal*: underground root systems
-*potential problems*: very dense and may exclude recreational pursuits like boating, fishing,
and swimming. Purple loosestrife is an example of a problem species.
Describe the general growth habits of, means of dispersal and potential problems caused by:
Submergent aquatic plants (both pondweeds and plants with whorled leaves) - ANS -*growth
habits*: grow mostly under water surface, pondweeds sometimes have floating leaves in
addition to their submerged leaves; whorled-leaf plants grow underwater with whorled leaf
attachments
-*means of dispersal*: pondweeds have extensive root systems, runners, and can also
reproduce from seeds; plants with whorled leaves can disperse when uprooted by breaking free
and getting moved by the wind
-*potential problems*: most pondweeds not nuisance except for curlyleaf pondweed and
sometimes sago pondweed; whorled leaf plants can uproot and break free easily and drift with
wind to clutter shoreline; Eurasian watermilfoil is an aggressive non-native that can affect
habitat and restrict recreation. Raking is required to remove these clutters.
Describe the general growth habits of, means of dispersal and potential problems caused by:
Free-floating and rooted floating-leaved aquatic plants - ANS -*growth habits*: occur on
water surface and can be free-floating or rooted with large floating leaves
-*means of dispersal*: free floating plants are easily windblown. rooted ones not so much
-*potential problems*: free-floating plants accumulate on shorelines and are difficult to control
in large waterbodies; rooted plants are rarely a nuisance.
Describe the general growth habits of, means of dispersal and potential problems caused by:
Free-floating, filamentous, and "rooted" algae - ANS -*growth habits*: found free-floating
(planktonic) or attached to submerged surfaces (filamentous or "rooted").
-*means of dispersal*: multiply rapidly in warm weather;
-*potential problems*: free-floating algae responsible for many nuisance algal blooms (release
toxin, low DO, blue-green algae); removing rooted algae can allow worse species to come in so
don't mess with them.
2 @COPYRIGHT 2025/2026 ALLRIGHTS RESERVED.
,List the advantages and disadvantages of chemical control of aquatic plants and algae -
ANS *Advantages*:
-offer longer-lasting control than some mechanical methods
-less physical labor
-ultimately cost less
-important tool for specific nuisance plants/algae such as Eurasian watermilfoil and purple
loosestrife
*Disadvantages*:
-restrictions on water use
-oxygen depletion and fish kills
-sudden nutrient release into water can lead to other plant or algae problems
-risk to people and nontarget organisms
Describe the beneficial roles of Wisconsin's fish populations. - ANS -maintain balanced
communities by feeding on aquatic plants, insects, and other fish & provide a food source for
natural predators
-fishing for food/sport is popular in WI and ddepends on healthy populations
-fish farms and hatcheries raise fish for food, feed, fertilizer, bait, and to release
List 5 types of situations in which fish control may be warranted - ANS -eliminating
undesirable or competing fish from fish rearing ponds
-removing exotic and other undesirable species from a waterbody
-thinning stunted fish to bring a population into balance
-eliminating fish from a hatchery water supply to prevent a potential reservoir of disease-
causing organisms
-treating fish spawning sites to prevent overpopulation of an individual species
3 @COPYRIGHT 2025/2026 ALLRIGHTS RESERVED.
, Explain why post-treatment management can be important in the long-term success of a
pesticide treatment project. - ANS -because when fish populations are lowered, density-
dependent population growth allows the population to rebound if not managed post-treatment
Know the Law: Who do you need to get approval from to conduct any chemical treatment for
fish control? - ANS WI DNR Aquatic Plant Management Program
List the 2 main reasons why mosquito control may be warranted. - ANS -nuisance
-disease
Describe the 4 stages of the mosquito life cycle, including the main structural features of each -
ANS -*egg*: laid in water, hatch in ~3 days, some laid on dry land and hatch when flooded
-*larva*: "wiggler", 4 instars with molting in between each, filterers, air tube to breath from
surface
-*pupa*: comma shaped, non-feeding, lasts a few days, contain respiratory trumpets,
"tumblers"
-*adult*: 1 pair wings, elongated probiscis, pair of antennae, males have bushy antennae while
females have short and sparse antennae
List the types of info you need about a mosquito species before you can develop an effective
program to control it. - ANS -the types and locations of breeding sites
-# of generations per year
-host preference of the females (what animals they prefer to get blood from)
-seasonal population levels and how rainfall affects them
-their flight range
-common resting areas
-whether the species can transmit pathogens that may be present in your area
-whether the mosquitoes carry pathogens that are present in wildlife populations
4 @COPYRIGHT 2025/2026 ALLRIGHTS RESERVED.
QUESTIONS AND ANSWERS GRADED A+
2025/2026
List the roles plants play in a healthy aquatic ecosystem. - ANS -producing oxygen
-preventing shoreline erosion
-lessening excess nutrients during growing season
-stabilizing lake bottom
-providing food and habitat for fish, waterfowl, and other aquatic animals
List ways that excessive plant growth can adversely affect the ecology and uses of a water body.
- ANS -harm ecology of aquatic ecosystem
-curtail or prevent recreational water uses (e.g. fishing, boating, swimming)
-impart tastes or odors to drinking water
-hamper water treatment operations
-adversely affect aesthetics, resort trade, and waterfront property values
-produce toxins that harm animals drinking the water
Describe the general growth habits of, means of dispersal and potential problems caused by:
Emergent aquatic plants - ANS -*growth habits*: rooted in shallow water, most growth above
water
1 @COPYRIGHT 2025/2026 ALLRIGHTS RESERVED.
,-*means of dispersal*: underground root systems
-*potential problems*: very dense and may exclude recreational pursuits like boating, fishing,
and swimming. Purple loosestrife is an example of a problem species.
Describe the general growth habits of, means of dispersal and potential problems caused by:
Submergent aquatic plants (both pondweeds and plants with whorled leaves) - ANS -*growth
habits*: grow mostly under water surface, pondweeds sometimes have floating leaves in
addition to their submerged leaves; whorled-leaf plants grow underwater with whorled leaf
attachments
-*means of dispersal*: pondweeds have extensive root systems, runners, and can also
reproduce from seeds; plants with whorled leaves can disperse when uprooted by breaking free
and getting moved by the wind
-*potential problems*: most pondweeds not nuisance except for curlyleaf pondweed and
sometimes sago pondweed; whorled leaf plants can uproot and break free easily and drift with
wind to clutter shoreline; Eurasian watermilfoil is an aggressive non-native that can affect
habitat and restrict recreation. Raking is required to remove these clutters.
Describe the general growth habits of, means of dispersal and potential problems caused by:
Free-floating and rooted floating-leaved aquatic plants - ANS -*growth habits*: occur on
water surface and can be free-floating or rooted with large floating leaves
-*means of dispersal*: free floating plants are easily windblown. rooted ones not so much
-*potential problems*: free-floating plants accumulate on shorelines and are difficult to control
in large waterbodies; rooted plants are rarely a nuisance.
Describe the general growth habits of, means of dispersal and potential problems caused by:
Free-floating, filamentous, and "rooted" algae - ANS -*growth habits*: found free-floating
(planktonic) or attached to submerged surfaces (filamentous or "rooted").
-*means of dispersal*: multiply rapidly in warm weather;
-*potential problems*: free-floating algae responsible for many nuisance algal blooms (release
toxin, low DO, blue-green algae); removing rooted algae can allow worse species to come in so
don't mess with them.
2 @COPYRIGHT 2025/2026 ALLRIGHTS RESERVED.
,List the advantages and disadvantages of chemical control of aquatic plants and algae -
ANS *Advantages*:
-offer longer-lasting control than some mechanical methods
-less physical labor
-ultimately cost less
-important tool for specific nuisance plants/algae such as Eurasian watermilfoil and purple
loosestrife
*Disadvantages*:
-restrictions on water use
-oxygen depletion and fish kills
-sudden nutrient release into water can lead to other plant or algae problems
-risk to people and nontarget organisms
Describe the beneficial roles of Wisconsin's fish populations. - ANS -maintain balanced
communities by feeding on aquatic plants, insects, and other fish & provide a food source for
natural predators
-fishing for food/sport is popular in WI and ddepends on healthy populations
-fish farms and hatcheries raise fish for food, feed, fertilizer, bait, and to release
List 5 types of situations in which fish control may be warranted - ANS -eliminating
undesirable or competing fish from fish rearing ponds
-removing exotic and other undesirable species from a waterbody
-thinning stunted fish to bring a population into balance
-eliminating fish from a hatchery water supply to prevent a potential reservoir of disease-
causing organisms
-treating fish spawning sites to prevent overpopulation of an individual species
3 @COPYRIGHT 2025/2026 ALLRIGHTS RESERVED.
, Explain why post-treatment management can be important in the long-term success of a
pesticide treatment project. - ANS -because when fish populations are lowered, density-
dependent population growth allows the population to rebound if not managed post-treatment
Know the Law: Who do you need to get approval from to conduct any chemical treatment for
fish control? - ANS WI DNR Aquatic Plant Management Program
List the 2 main reasons why mosquito control may be warranted. - ANS -nuisance
-disease
Describe the 4 stages of the mosquito life cycle, including the main structural features of each -
ANS -*egg*: laid in water, hatch in ~3 days, some laid on dry land and hatch when flooded
-*larva*: "wiggler", 4 instars with molting in between each, filterers, air tube to breath from
surface
-*pupa*: comma shaped, non-feeding, lasts a few days, contain respiratory trumpets,
"tumblers"
-*adult*: 1 pair wings, elongated probiscis, pair of antennae, males have bushy antennae while
females have short and sparse antennae
List the types of info you need about a mosquito species before you can develop an effective
program to control it. - ANS -the types and locations of breeding sites
-# of generations per year
-host preference of the females (what animals they prefer to get blood from)
-seasonal population levels and how rainfall affects them
-their flight range
-common resting areas
-whether the species can transmit pathogens that may be present in your area
-whether the mosquitoes carry pathogens that are present in wildlife populations
4 @COPYRIGHT 2025/2026 ALLRIGHTS RESERVED.
