clay caterpillar predation bioassay

Knowledge graph centered on clay caterpillar predation bioassay with 36 nodes and 124 connections. Top connected: Ligusticum porteri, Populus, elevational gradients, Populus tremuloides, Polemonium.

Method synopsis

Artificial prey made from green modeling clay are deployed on tree branches to estimate bird attack rates over a standardized time period. Attack marks on clay allow identification of predator type and quantification of predation pressure.

Synthesized from method descriptions across 1 paper using this protocol.

Procedure from a recent peer-reviewed implementation

Steps below were extracted from the most recent peer-reviewed implementation of this protocol in the corpus — Decomposing an elevational gradient in predation by insectivorous birds (2024), Ecosphere. Implementations in other papers (listed below) may differ.

1. Prepare clay caterpillars
   Create 50-mm long and 5-mm wide model clay caterpillars using green nontoxic modeling clay (Sargent Art) extruded with clay extruder (Walnut Hollow), then attached to tree branches using super glue (Loctite)
   Quantities: 20 caterpillars per site, 2-3 m tall quaking aspen saplings (Salicaceae: P. tremuloides) separated by at least 1 mDuration: Preparation prior to deploymentConditions: Caterpillars placed on branches 1-2.5 m from ground, 10-30 cm away from branch tip
   Equipment: Clay extruder (Walnut Hollow), Green nontoxic modeling clay (Sargent Art), Super glue (Loctite)
2. Deploy caterpillars
   Place two caterpillars on tip surface of branches at each of 10 trees per site, with caterpillars pruned around to prevent contact with clay and replaced following any predator attack
   Quantities: 20 caterpillars total per site (2 caterpillars × 10 trees × 4 sites × 5 valleys), totaling 76 attack rates across 4 valleys × 4 sites × 4 deployments + 1 valley × 4 sites × 3 deployments = 64 + 12 = 76 totalDuration: 14-day period in summer 2020Conditions: August 2020, during peak bird activity and postfledging period
   Equipment: Clay caterpillars, Super glue
3. Monitor caterpillars
   Check caterpillars for attack four separate times (day 3, day 5, day 7, day 14 of deployment), recording attacks and replacing attacked caterpillars with new ones in same location. Missing caterpillars (0.003% across deployed caterpillars) were not recorded as attacks

Typical Equipment

• Clay extruder (Walnut Hollow)
• Green nontoxic modeling clay (Sargent Art)
• Super glue (Loctite)

Output Measurements

• attack rate
• proportion of caterpillars attacked

Papers Using This Protocol (1)

Species Studied With This Protocol