Hypercarnivorous apex predator could provide ecosystem services by dispersing seeds

Area of Science:

• Ecology
• Zoology
• Botany

Background:

• Apex predators, such as large "hypercarnivorous" felids, are crucial for food webs and ecosystem functioning.
• Their roles typically involve competition and predation, shaping ecological dynamics.

Purpose of the Study:

• To investigate the potential of cougars (Puma concolor) as secondary seed dispersers.
• To determine if cougars facilitate plant-species interactions at the base of the food web.

Main Methods:

• Analysis of cougar scats (feces) to identify ingested seeds.
• Quantification of seed numbers and types, specifically from the Eared Dove's diet.
• Comparison of seed germination rates from cougar scats versus dove gizzards.

Main Results:

• Cougars ingested and dispersed a significant quantity of seeds (31,678 seeds in 123 scats).
• Seed germination rates from cougar scats were comparable to those from dove gizzards.
• Estimated annual seed dispersal by cougars could reach approximately 5,000 seeds per km(2).

Conclusions:

• Strictly carnivorous felids, like cougars, can act as effective long-distance seed dispersers.
• This highlights overlooked ecological functions of apex predators in ecosystem structuring and functioning.
• Cougars mediate plant dispersal, establishing non-herbivore-mediated interactions with plant species.