Quizzes

Question 1

Estuary Definition:

Answer 1

body of water where a river meets the sea and where fresh and saltwater mix

Question 2

4 categories of carbon sources:

Answer 2

Ocean sources
River sources
Emergent veg
Submergent veg

Question 3

4 most abundant ions in salt water:

Answer 3

Cl-
Na+
Mg
SO4

Question 4

General salinity range:

Answer 4

0.5-30 “BRACKISH”

Question 5

Why does saltwater sink relative to freshwater

Answer 5

Saltwater is denser due to the salt concentration within the same volume of water

Question 6

3 tidal cycles

Answer 6

Semi-Diurnal Tide: two almost equal high tides and two low tides each day
Diurnal Tide: only one high and one low tide each day
Mixed Tide: two uneven tides a day

Question 7

What does Burrard Inlet have

Answer 7

Mixed

Question 8

3 factors that influence tides in estuary

Answer 8

Amount of freshwater input
Tidal patterns and current
Geology of area
Climate
Winds and weather

Question 9

Geology classes of estuary

Answer 9

Coastal plane/flooded river valley
Delta
Fjord
Tectonic
Bar-built
Lagoon

Question 10

Stratification and Fresh-Seawater Circulation classes of estuary

Answer 10

Salt-wedge (most stratified (least mixed))
Fjord
Slightly stratified (deep estuaries)
Vertically mixed (most mixed, shallow estuaries)
Freshwater

Question 11

What geologic class of estuary is associated with West Coast rivers

Answer 11

Flooded river valley

Question 12

Howe Sound geologic class

Answer 12

Fjord

Question 13

Based on the estuary stratification classification, () estuaries have the highest, degree of stratification, and () estuaries are the most well-mixed

Answer 13

salt-wedge, vertically-mixed

Question 14

Stratification class with rapidly flowing river discharge into the ocean where tidal currents are relatively weak

Answer 14

Salt-wedge

Question 15

Stratification class of geologically classified Fjord

Answer 15

Fjord

Question 16

Factors that control Fjord stratification

Answer 16

Sill acts as a natural barrier for denser saltwater

Question 17

Rank the species of Pacific salmon based on the time spent in the estuary as juveniles before moving offshore into the marine environment (in order of increasing time spent)

Answer 17

Pink
Chum
Chinook

Question 18

What are the two dominant life-history strategies of Chinook?

Answer 18

Ocean type - move into the estuary sooner and spend an extended amount of time growing
Stream type - spend longer in the stream growing before going to the estuary

Question 19

Which occupies the estuary longer?

Answer 19

Ocean

Question 20

Two life functions carried out by juvenile Pacific salmon in estuary habitats?

Answer 20

Need to undergo physical transformations from freshwater to saltwater fish as juveniles

Need to undergo physical transformations from saltwater to freshwater fish as spawners

Consume prey and grow large enough to migrate to the ocean

Imprinting on their natal streams
(concentrations of the hormone thyroxine =facilitate olfactory imprinting)

Question 21

What line(s) of evidence suggests that some juvenile Chinook salmon rely on estuary habitats for an extended period of time before migrating off-shore?

Answer 21

Chinook salmon were recorded using tidal channels - presence detected over time, increasing fork length and growth

Mark and recapture surveys saw juvenile chinook return to tidal channels over several tide cycles

Question 22

The scientific name of eelgrass?

Answer 22

Zostera marina

Question 23

The main way that eelgrass reproduces?

Answer 23

Reproduce asexually from rhizomes

Question 24

Ecological Services and Functions of eelgrass

Answer 24

1. carbon capture and storage (sequestration!)
2. removal of polluting nutrients, compounds
3. trapping of suspended sediment, thereby improving water clarity and enhancing eelgrass growth
4. wave attenuation
5. reduces nearshore erosion by anchoring sediment with its spreading rhizomes
6. provides food, breeding areas, and protective nursery habitat for fish, shellfish, crustaceans and many other animals

Question 25

Human Impacts on Eelgrass

Answer 25

Dredging and filling associated with the construction of harbours and ports Excess nutrient loading and chemical contamination Logging Land development Oil spills Docks create shading problems for eelgrass beds Anchoring of recreational boats along the nearshore disturbs rhizomes Boat propellers cut eelgrass beds in shallow waters Invasives - European green crab

Question 26

Burrard Inlet, what are three (3) distinct types of major stressors that have contributed to eelgrass declines?

Answer 26

1. Dredging/infilling 2. Eutrophication/water quality/chemical contamination 3. Logging, oil spills, docks, anchoring, boat propellors

Question 27

Factors Influencing eelgrass restoration Success

Answer 27

Proximity to natural eelgrass bed Site selection (substrate, depth, current or wave disturbance) Quality of donor stock Light Salinity Temperature

Question 28

a practical and common metric used to determine if a restored eelgrass bed is approaching reference condition?

Answer 28

Shoot density (m2)

Question 29

Canada Goose Scientific name?

Answer 29

Five sub-species found in BC: B. c. canadensis – Atlantic B. c. moffitti – Great Basin B. c. leucoparia – Aleutian B. c. occidentalis – Dusky B. c. fulva - Vancouver

Question 30

Breeding goose on Vancouver Island?

Answer 30

(no historical records of large nesting populations)

Question 31

What law protects Canada geese AND what level of government is responsible for management decisions related to Canada geese?

Answer 31

Migratory Birds Convention Act (1994) MBCA Federal government – Canadian Wildlife Service (CWS) within Environment Canada

Question 32

What are the four (4) politically-acceptable mechanisms for managing geese populations in BC?

Answer 32

Hunting Damage/Danger Permit Addling (oil pricking similar... basically a means to sterilize eggs) First Nations harvesting (Charity permit is a use for the meat, but not a management tool) Exclosure fencing

Question 33

What stage in the life cycle of Canada Geese are herbivory pressures on native marsh vegetation greatest and why?

Answer 33

During molting from mid-June to mid-July as they concentrate in large groups and cannot fly, hence their local grazing pressure is most intense. Second greatest time is when young birds are maturing as energy demands are high (partial marks)

Question 34

What characteristics of human-modified landscapes have contributed to explosive population growth of Canada geese?

Answer 34

Geese have 3 basic habitat requirements: Water, open space, and food. Human-modified landscapes include the conversion of forests to an abundance of open, green space in the form of agricultural land, parks, golf courses and other features that support geese populations. Across our urban landscape, we have also nearly eliminated hunting opportunities, therefore there is no natural predator