Fish Migration: concepts, definitions and mechanisms … · Fish Migration: concepts, definitions...
Transcript of Fish Migration: concepts, definitions and mechanisms … · Fish Migration: concepts, definitions...
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Vismonitoring in grote rivieren
Erwin Winter
Nederlands Instituut voor Visserijonderzoek
februari 2002
Fish Migration:
concepts, definitions and mechanisms
Erwin Winter
IMARES, Wageningen UR
18 June 2015
FITFISH
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Fish Migration: contents
o Importance of migration, basic concepts and definitions
o Costs and benefits of migration
o Variation in migratory patterns: concepts redefined
o Mechanisms of migration
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Spatial use:
Areas used by populations: how separate are populations?
Insight in scale and patterns of underlying movements
Migration:
Cyclic movements in which a large part of the population
takes part (time scale: from diel, seasonal to life cycle)
Dispersal:
Movements of individuals away from each other
(nett distance between individuals increases)
Predictability: from fixed to opportunistic (nomadic)
Important consequences for management of ‘stocks’
Movements: migration & dispersal
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Migratory shifts in habitat use
Life cycle (ontogenetic shifts):
Requirements change
Temporal cycle (shifts in habitat favourability):
Day-night
Seasonal:
- summer-winter (temperate)
- dry-rainy (tropical)
Habitats (end goals) and corridors (connections between habitats)
Spawning
Feeding
Refuging
Eggs
Larvae
Juveniles
Adults
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Variation in migratory patterns is huge!
Between species (from extremely sedentary to trans-oceanic)
Bullhead: < 10 m x
Great white shark:
Roundtrips of
> 20.000 km !
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Migratory patterns in Salmon (anadromous)
Mixed feeding
Separate spawning
long migrations + no dispersal (strong homing) =
many separate populations !!
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Lateral migration: flood plains
Lower Volga in Russia
Photos: Konrad Gorski
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Waarom de Wolga?
400 km 30 km
Lower Volga in Russia
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Lower Volga in Russia
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Lower Volga in Russia
4-year field study to test FPC: Wageningen Univ, Utrecht univ. IMARES
For spawning fish: within floodplain
lateral movements appear to dominate
Photos: Konrad Gorski
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Lack of migration: Lake Victoria
Life history traits cichlids:
Mouth-breeding (parental care)
No migration (resident)
No dispersal
Strong sexual selection
Local circumstances:
Rocky ‘islands’ in sandy ‘sea’
Relatively young system
Lack of lacustrine species
Extreme separation
between populations
->
species flock formation
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Migratory variation in Salmon
Between populations:
Land-locked (no sea-phase)
vs.
Migratory (anadromous)
Within population (alternative strategies):
Migration (females and large males)
vs.
Sedentary (small ‘sneaking’ males)
this semelparous species: individual patterns genetically based
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Migratory variation in ide (cyprinid)
Great white shark:
Roundtrips of
> 20.000 km !
Life history characteristics:
Potamodromous
Iteroparous
long living
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Examples of
individual patterns
Highly variable
Continuum from
resident to >200 km
(as in River Elbe
F. Fredrich)
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Long-term individual patterns (3 years):
each individual behaves different from others …
Vecht
p aai groei w in t er
b ovenst room s
b ened enst room s
Meren (Zw ar t e,
Ket el- en IJssel-)
St uw + vist rap
Rivierm ond ing
1998
km
1999 2000 1998 1999 2000 1998 1999 2000 1998 1999 2000
135
145
155
165
175
185
195
205
Upstream
section
Downstream
section
Weir & Fishway
River mouth
Downstream
lakes
… but very similar in each year!
spawn grow
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Mechanisms of migration (water currents)
Oceanography plays an important role (for example eels)…
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Mechanisms of migration (water currents)
In coastal areas (for example larval plaice)…
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Mechanisms of migration (water currents)
Where larval plaice shows a remarkable pattern:
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Selective tidal transport
From sea to rivers for poor swimmers
Low tide sea river
0
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Selective tidal transport
From sea to rivers for poor swimmers
Flood sea river
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Selective tidal transport
From sea to rivers for poor swimmers
Flood zee rivier
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Selective tidal transport
From sea to rivers for poor swimmers
Flood zee rivier
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Selective tidal transport
From sea to rivers for poor swimmers
High tide sea river
0
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Selective tidal transport
From sea to rivers for poor swimmers
Ebb sea river
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Three categories of swimming capacities:
Sustained: long duration without fatique
Prolonged: intermediate duration resulting
in fatique dependent on Temperature and Oxygen
Burst speed (<15 s):
only for emergency
increased vulnerability
(rebuilding stored glycogen)
dependent on temperature
(anaerobic)
Swimming capacity to overcome distances and barriers
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Swimming capacity
From Katopodis & Gervais (2012)
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Swimming stride by stride
For lenght x and temperature y and tail beat frequency Fxy(s-1),
then Flt at other lenghts l an temperature t burst speed can be
calculated (Videler & Wardle 1991):
Flt = Fxy (0.87(l-x)/10) (2(t-y)/10)
Maximum burst speed Ult (m s-1) for other lengths l and
temperatures t can be determined if species specific stride
length Sl is known:
Ult = Sl.Flt
Burst swimming capacity
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Mechanisms of migration (cues)
Navigation and oriëntation cues
Taxes = directed movements
o Physical:
Phototaxis : light direction
Geotaxis : gravity
Rheotaxis : water currents
Magnetotaxis : earth magnetic field
Sound : coral reefs, shorebreak
o Scalar: gradients in
Salinity
Temperature
Turbidity
Olfactory clues
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Variation in migratory patterns is huge!
Between species (from extremely sedentary to trans-oceanic)
Bullhead < 10 m
x
European eel > 6000 km
Mixed
spawning Leptocephalus
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Many cues used simultaneously (salmon)
Large scale movements:
Magnetic field
rheotaxis
Selecting river:
Olfaction by imprinting
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Sea lamprey (specific pheromone!)
Bizarre life cyle:
Eggs in gravel rivers
Larvae (ammocoetae) in sediments
After 6-8 year (15-20 cm) to sea
Rapid growth as parasite on fish
Migrate upstream rivers to spawn
Selection of the river?
Adult lamprey (up to 1 m) choose
rivers that contain pheromones
released by larvae (not necessarely
natal river, but a suitable river)
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Mechanisms of migration (role of learning)
o Imprinting of substances in water of juvenile anadromous fish
o Sun compass and magnetic field most likely for long-distance
navigation (salmon, eels)
o Learning by experience (in ide?)
o Learning the route from other fish: “cultural transmission”
Juvenile grunts follow fixed migration routes stable over generations in
evening movements from shelter to feeding ground; herring migrations
Routes based on landmarks? Routes learned?
Experiments show that naïve individuals learn from experienced
individuals through dummy migrations
Much is still unknown !!!
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Vismonitoring in grote rivieren
Erwin Winter
Nederlands Instituut voor Visserijonderzoek
februari 2002
Management issues
& Research methods on
migration and dispersal
Erwin Winter
Netherlands Institute for Fisheries Research
Animal Sciences Group, Wageningen UR
11 Oktober 2005
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Vecht
Rhine
Meuse
Dams & Weirs
Fishways
100 km
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Telemetry experiments
1998-2004 30 Detection stations
25
12
40 9
61
13
160 Ide (Leuciscus idus)
NEDAP-transponders
Life span 3-4 years
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NEDAP-RIZA transponder systeem
Batteries
Print-
Glass card Ferrite-bar Coil
Antenna
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Passage behaviour at fishways
Detection
station
fishway
flow
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Passage success & attraction flow
0
50
100
150
200
250
300
350
0 50 100 150 200
0
0.1
0.2
0 50 100 150
River flow (m3/s) River flow (m3/s)
Individual delay (hrs) Passage success
Ratio
flow fishway /
flow river
Weir free-flowing
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Detection stations at Linne and Lith
weir
Hydropower
Station Fishway
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Transponder experiment 2002
Electrovisserij voorjaar 2002
Stevensweerd
Spui Dordtse Kil
Capelse Veer
Sambeek
Balgooij
Haringvliet Oude Maas
Linne
Afferden
Lith-Alphen
The Netherlands
North Sea
Belgium Germany
Belfeld-Reuver
Station entire river width
Station entrance hydropower
Station in fishway
Monitoring commercial fishery
River Meuse
Release site transpondered eel
Ohe Laak
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Transponders and surgical procedure
Transponder NEDAP-TRAIL, RIZA
63x14 mm, 26.5 g (air), 16 g (water)
Anaesthesia: 2-phenoxy-ethanol (0.9 ml l-1)
Mid-ventral incision: 2-3 cm (in body cavity)
Wound closing: Cyanoacrilate adhesive &
biological bandage (Baras & Jeandrain 1998)
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Hightech tags
Archival tags:
Stores data on temperature, pressure etc.
Read out after recapture
Combination acoustic/radio tags:
Can be used in wide range of habitats, sea-river
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Markers
- Biological:
Genetic
Fatty acids
Isotopes
- Chemical:
Strontium-calcium to determine sea vs. freshwater habitats
Tracers, e.g. contaminants
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- Juveniles/small fish:
individual tagging methods mostly lacking
- Tropical fish:
very species rich
hardly any information on role migration for most fishes
difficult to handle, perform surgery
Gaps in knowledge and methods
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Fishway at Amerongen