Final answer:
If a species exceeds its carrying capacity, it will likely face a decline in population size as resources get depleted; its numbers will eventually level off or drop below carrying capacity. Populations tend to fluctuate around this capacity due to environmental pressures and resource availability.
Step-by-step explanation:
When a particular species exceeds its carrying capacity, the resources available to it become overstretched. In the short term, this can happen due to rapid growth or environmental fluctuations. However, exceeding carrying capacity cannot be sustained for long. The end result for the species is likely to be a reduction in population size as factors like famine, disease, and increased predation work to lower the number of individuals back down towards or even below the carrying capacity.
Populations typically exhibit logistic growth, where they increase rapidly when resources are abundant but slow down and level off as resources become scarcer, balancing around the carrying capacity. In real ecosystems, populations might temporarily overshoot their carrying capacity, leading to resource depletion and higher mortality, which then causes the population to decline again.
Depending on the species and the ecosystem, fluctuations can occur around the carrying capacity as populations respond to changes in resource availability and other environmental pressures such as climate variation, natural disasters, and interspecific competition.