SAMPLE COMPOSITION: PARASITE ECOLOGY'S DIRTY LITTLE SECRET.

Area of Science:

• Ecology
• Parasitology
• Ichthyology

Background:

• Sample homogeneity is crucial for comparative studies.
• Including diverse host demographics can reduce sample comparability.
• Sunfish (Lepomis spp.) are suitable models for studying host-parasite interactions.

Purpose of the Study:

• To determine if excluding larger hosts or including smaller, related species improves sample homogeneity.
• To evaluate the effectiveness of cumulative performance curves in assessing sample comparability.
• To identify reliable determinants of infracommunity similarity in fish samples.

Main Methods:

• Subdividing mixed sunfish samples.
• Utilizing cumulative performance curves to analyze diversity and richness.
• Employing nonmetric multidimensional scaling (NMDS) to compare infracommunity structures.

Main Results:

• Excluding larger sunfish reduced sample aggregation.
• Mixed-species samples of smaller fish showed lower aggregation than single-species samples.
• Sunfish size was a more significant factor in infracommunity similarity than species identity.

Conclusions:

• Cumulative aggregation curves effectively delineate homogeneous subsamples.
• Stratified sampling by size, including congeneric/confamilial hosts, can offset smaller sample sizes.
• Host size is a critical factor for comparable ecological and parasitological studies.