What is the typical clutch size in K-strategists?
K-selected organisms generally produce a small clutch because each offspring receives substantial resources. Energy that could create many propagules is instead invested in larger young, prolonged development, protection, or feeding. This trade-off tends to raise juvenile survival in stable, crowded environments where successful competition matters more than rapidly flooding an empty habitat with offspring. The r/K framework is best treated as a continuum. At one end, rapid development and many inexpensive offspring suit transient opportunities; at the other, slower development and greater investment per offspring can improve success near environmental limits. Modern life-history theory tests the underlying trade-offs directly rather than assigning every species to a fixed box. The conclusion follows from tracking how density or age changes the rates experienced by individual organisms. Field evidence should therefore be compared with the model assumptions before extending the conclusion to every species, habitat, or time period. Interpreting the example at the appropriate population scale keeps the causal mechanism distinct from a simple correlation or an absolute rule.
Ref: Ecology: Concepts and Applications, Molles, 9th Ed., Ch. 12