Aquatics - Breeding Strategies - Revision Cards in Other Other

r and K strategists

r

K

1 of 10

2 of 10

any behaviour performed by parents that help the development of young
Embryonic cannibalism = the largest foetus eats its siblings in the womb until only it survives

3 of 10

The fish lays their eggs anywhere, there is no parental care and parents may even eat their own eggs
Usually produce around 300 eggs
Short hatch time
e.g., Koi Carp
Advantages: high genetic diversity, uses low energy levels, high amounts of eggs give a higher change for success
Disadvantages: low chance of success as most eggs will fail to hatch, eggs predated on

4 of 10

pick one general spot to lay sticky eggs
lay fewer eggs than egg scatterers
some species care for their young
Don't eat their own eggs
Advantages: lack of parental care so less energy spent by parents, eggs laid in a suitable place so that tides/currents potentially move them if the substrate is loose.
Disadvantages: lack of parental care leading to less chance eggs will hatch, easily predated if not hidden when laid.

5 of 10

6 of 10

build a nest made of plant debris and saliva, or they may dig a pit in the substrate
take care of their young
Advantages: protection of the eggs during the vulnerable stages
Disadvantages: takes energy to build a nest, do not survive without the caregiving parent

7 of 10

parent carries and guards eggs in their mouth
e.g., Cyphotilapia frontosa
Ovophiles or larvophiles
- Ovophiles pick up the fertilised eggs and carry them in their mouths even when they hatch
- Larvophiles, guard and protect eggs till they hatch and then pick them up in their mouth
Produce around 20-50 fry
Advantages: higher success rate as young more likely to survive
Disadvantages: low genetic diversity, energy costs high

8 of 10

individual changes sex during some point in its life
Advantages: higher likelihood of meeting a mate, protects against inbreeding
Disadvantages: takes a long time to change sex

9 of 10

10 of 10