GoConqr has a new look! Let us know what you think.

Sign up free

Quiz

Fish Migrations

sophie waddington 19 questions

Take the quiz

This quiz has question types that open in the usual player.

Questions in this quiz (19)

  1. 1Why do fish migrate?
    > to move [blank_start]breeding[blank_end] grounds (mating grounds); bring mature adults together
    > to follow [blank_start]food[blank_end] availability; seasonal prey items may change or move
    > to escape from adverse [blank_start]environmental[blank_end] (al) conditions; e.g. ocean warming due to El [blank_start]nino[blank_end] years
    > to follow favourable environmental conditions e.g. ocean temperature [blank_start]isotherms[blank_end] (pl; term coined by Alexander von humboldt regarding temp)

    NOTE: [blank_start]food[blank_end] may also be mobile; may be following a particular species, fish themselves are growing so have to move to areas where their food is bigger

    Migrations occur in a wide range of marine fish species, with a number of very well known examples
    - breeding migrations of European eels to the [blank_start]Sargasso[blank_end] Sea
    - the return of the european elvers to to European estuaries
    - ascending [blank_start]rivers[blank_end] from the sea to breed in many salmonid species
    - breeding migrations of herring shoals
    - new discoveries of [blank_start]long[blank_end] distance migration of great whale sharks

    1. Abreeding
    2. Bfood
    3. Cenvironmental
    4. Dnino
    5. Eisotherms
    6. Ffood
    7. GSargasso
    8. Hrivers
    9. Ilong
  2. 2[blank_start]Diadromous[blank_end] Migrations = migrations between the sea and [blank_start]fresh[blank_end] water

    There are 2 types of diadromous migrations:

    1. [blank_start]catadromous[blank_end] = a life cycle in which the fish grows to maturity in fresh water but breeds in the sea e.g. in [blank_start]eels[blank_end]

    2. [blank_start]anadromous[blank_end] = a life cycle when the fish grows to maturity in the sea but breeds in fresh water e.g. seen in [blank_start]salmon[blank_end]
    1. ADiadromous
    2. Bfresh
    3. Ccatadromous
    4. Deels
    5. Eanadromous
    6. Fsalmon
  3. 3Example of [blank_start]Catadromous[blank_end] migrations: Spawning migrations of [blank_start]European[blank_end] eels, Anguilla anguilla
    > breed in the [blank_start]sea[blank_end] and then ascend to rivers to grow to maturity in fresh water as '[blank_start]yellow[blank_end]' eels (colour)
    > American eels do the same but in north [blank_start]America[blank_end]
    > adult eels undergo physiological changes to become '[blank_start]silver[blank_end]' eels (colour) and then migrate downstream to the sea and cross the Atlantic Ocean to the [blank_start]Sargasso[blank_end] Sea where they breed and die

    > so european eels are said to be [blank_start]semelparous[blank_end]: semelparous species are those that have [blank_start]1[blank_end] reproductive episode before dying (essentially die once bred)

    FACT: it is thought all european eels go to the same location to breed, the [blank_start]Sargasso[blank_end] Sea, however this has never been recorded.
    1. ACatadromous
    2. BEuropean
    3. Csea
    4. Dyellow
    5. EAmerica
    6. Fsilver
    7. GSargasso
    8. Hsemelparous
    9. I1
    10. JSargasso
  4. 4The [blank_start]Sargasso[blank_end] Sea: thought to be where all european eels go to breed
    - an area of the Atlantic ocean, to the North-east of the Caribbean sea bounded not by land but by ocean [blank_start]currents[blank_end]
    - off the coast of the US, around bermuda
    - research has shown that eels breed with other [blank_start]eels[blank_end] from the source (provenance)
    - the movement of some of these fish can be monitored via implant trackers associated with [blank_start]floats[blank_end] > when the fish fries the tag will hopefully float to the surface and wash up where it can be retrieved and information gathered > not always successful
    > it still has [blank_start]not[blank_end] be been proven that all european eels go to the Sargasso sea to [blank_start]breed[blank_end]

    The trackers in [blank_start]european[blank_end] eels can also be used to tell us what has [blank_start]eaten[blank_end] the eels; this has revealed it is a dangerous life for eels at sea
    > can deduce by looking at [blank_start]pressure[blank_end] readings (where the animal is in the water column)
    > a typical eel oscillates between 400m in night and 800m in a day ([blank_start]diurnal[blank_end] migration in the water column)
    > whereas if an eel was predated by a short-finned pilot whale the readings would show much deeper dives and a higher body [blank_start]temperature[blank_end] (for it is a mammal)
    1. ASargasso
    2. Bcurrents
    3. Ceels
    4. Dfloats
    5. Enot
    6. Fbreed
    7. Geuropean
    8. Heaten
    9. Ipressure
    10. Jtemperature
    11. Kdiurnal
  5. 5Larval eel migration: migration of [blank_start]european[blank_end] eel larvae following breeding in the [blank_start]Sargasso[blank_end] sea
    > larval eels called the leptocephalus larva are carried back across the atlantic ocean in the [blank_start]Gulf[blank_end] Stream
    > this journey takes 2-3 [blank_start]years[blank_end]
    > these larvae are too [blank_start]small[blank_end] to swim in the ocean so they are simply carried by ocean [blank_start]currents[blank_end]
    > they develop to [blank_start]glass[blank_end] eels (silica) that enter estuaries = transparent elvers (young eel)
    > juvenile eels ascend rivers where they [blank_start]grow[blank_end] and mature
    > they may reach 1m in length and spend more than 50 years in the [blank_start]fresh[blank_end] water before they return to the sea to [blank_start]breed[blank_end]
    1. Aeuropean
    2. BSargasso
    3. CGulf
    4. Dyears
    5. Esmall
    6. Fcurrents
    7. Gglass
    8. Hgrow
    9. Ifresh
    10. Jbreed
  6. 6Eel Migration and Aquaculture
    - eel aquaculture ([blank_start]aquafarming[blank_end]) is a multi-million pound industry
    - the life cycle of [blank_start]european[blank_end] eels means that at present the cycle cannot be 'closed' in aquaculture as they need to migrate to the [blank_start]sea[blank_end]
    - the industry is dependent on a supply of transparent elvers harvested from the wild
    - in the Uk the River [blank_start]Severn[blank_end] (7) is the main source of these elvers which enter the river the [blank_start]winter[blank_end] (brrr) and the activity provides a livelihood for a number of elver fishermen
    - the fishermen go along with nets and catch the elvers coming [blank_start]up[blank_end] the stream

    BUT: there is concern that the industry may not be sustainable
    > [blank_start]european[blank_end] eel fisheries conservation group has stated that 'to many elvers are being taken from european waters)
    > numbers of elvers have [blank_start]decreased[blank_end] in the River Severn and the elver fishing is part of a 'River severn strategy document' to ensure the sustainability of the fisher'
    - the decline of elvers may [blank_start]not[blank_end] be due to fishing, as they were exploited more in the past
    - factors affecting elver numbers are thought to include: climate [blank_start]change[blank_end], habitat loss and obstruction of [blank_start]water[blank_end] ways

    we know very little about the marine stage of the eel's lifecycle
    1. Aaquafarming
    2. Beuropean
    3. Csea
    4. DSevern
    5. Ewinter
    6. Fup
    7. Geuropean
    8. Hdecreased
    9. Inot
    10. Jchange
    11. Kwater
  7. 7Eel Management Strategy
    > eel fishery is the largest commercial inland fishery (by value) in the [blank_start]UK[blank_end]
    > the environment agency manages the [blank_start]eel[blank_end] fishery
    > EA licensing of eel fisherman provides valuable income and employment to the rural community
    > there are lots of initiatives to put in eel friendly waterway [blank_start]stairs[blank_end] for eels to get around obstacles that may be causing decline
    1. AUK
    2. Beel
    3. Cstairs
  8. 8Example of [blank_start]Anadromous[blank_end] fish migrations: grow to maturity in the [blank_start]sea[blank_end] and enter fresh water to [blank_start]breed[blank_end]
    > migratory salmonids such as the Atlantic [blank_start]Salmon[blank_end] (Salmo salar) and the sea [blank_start]trout[blank_end] (Salmo trutta) spend their juvenile stages (called a [blank_start]parr[blank_end], like golf) in fresh water
    > this typically lasts 2-3 [blank_start]years[blank_end] (same duration as eels being carried in ocean currents)
    > after [blank_start]2[blank_end]-3 years the fish migrate [blank_start]down[blank_end] rivers as smolts
    > these [blank_start]smolts[blank_end] enter the sea where they grow to adults over one or more sea winters
    > eventually come inshore to [blank_start]breed[blank_end]
    > [blank_start]smolts[blank_end] (mature salmonids) undergo changing [blank_start]physiology[blank_end] in order to cope with change from fresh water --> estuarine --> marine conditions
    1. AAnadromous
    2. Bsea
    3. Cbreed
    4. DSalmon
    5. Etrout
    6. Fparr
    7. Gyears
    8. H2
    9. Idown
    10. Jsmolts
    11. Kbreed
    12. Lsmolts
    13. Mphysiology
  9. 9Salmon Movements at Sea
    > atlantic salmon leaving east coast US and UK waters migrated to waters off [blank_start]greenland[blank_end] (not iceland)
    - sea trout (the migratory form of the native brown trout) migrate around UK coastal waters, keeping relatively [blank_start]close[blank_end] to shore
    - we know little about what they do during the adult marine stage compared to how much we know about the fresh water stage
    - as soon s they enter the [blank_start]marine[blank_end] environment we know they migrate over to greenland areas but we are unsure as to what they are doing
    1. Agreenland
    2. Bclose
    3. Cmarine
  10. 10Another [blank_start]anadromous[blank_end] migration example: mature in sea and breed in fresh water: [blank_start]Sturgeon[blank_end] (Acipenser spp)
    - large > reaching 5m in length and over 1 ton in weight
    - long-lived (beluga live up to 150 years)
    - anadromous migrations (breed in [blank_start]fresh[blank_end] water)
    - primitive (cartilaginous bony plates instead of [blank_start]scales[blank_end])
    - found in the [blank_start]northern[blank_end] hemisphere
    - in late spring, sturgeons swim up river to spawn in clean [blank_start]fast[blank_end] flowing streams
    - females deposit several million [blank_start]sticky[blank_end] eggs on gravel
    - fecundity is directly proportional to the [blank_start]size[blank_end]
    - juveniles migrate to [blank_start]brackish[blank_end] (estuarine) and then to the sea
    - take 10 [blank_start]years[blank_end] to mature
    - economically important > valued for the meat, [blank_start]roe[blank_end] (caviar), isinglass (kind of [blank_start]gelatin[blank_end] used in brewing) and as sport trophies
    - all Species are now protected under CITES
    - in [blank_start]1998[blank_end] (me) illegal trade of caviar (roe) totalled over 220 tonnes (WWF)
    - sustainable stripping of caviar ([blank_start]roe[blank_end]) from ripe sturgeon is now being undertaken
    1. ASturgeon
    2. Banadromous
    3. Cfresh
    4. Dscales
    5. Enorthern
    6. Ffast
    7. Gsticky
    8. Hsize
    9. Ibrackish
    10. Jyears
    11. Kroe
    12. Lgelatin
    13. M1998
    14. Nroe

Information

Description
Marine Vertebrates Quiz on Fish Migrations, created by sophie waddington on 13/05/2018.
Language
English
Views
2
Rating
No ratings yet
Rate this quiz
Rate this quiz

Feedback

What is it about?

What do you think of the new look?

How do you like it?