Stable isotope enrichment marking of aquatic insects (Animalia)

Knowledge graph centered on Stable isotope enrichment marking of aquatic insects (Animalia) with 17 nodes and 62 connections. Top connected: Spruce, Lepidoptera, aquatic insects, Baetis, Measuring dispersal in a metapopulation using stab.

Method synopsis

A technique to mark developing aquatic insect larvae by enriching their habitat with heavy nitrogen isotopes (15N), which becomes incorporated into larval tissues and persists through metamorphosis to adults. Adults can then be identified as originating from the enriched habitat based on their isotopic signature.

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 — Measuring dispersal in a metapopulation using stable isotope enrichment: high rates of sex-biased disperal between patches in a mayfly population (2003), Oikos. Implementations in other papers (listed below) may differ.

1. Add stable isotope enrichment
   Five grams of 15N enriched ammonium chloride (Isotech, Inc., minimum 99% 15N) was added to Avery pond using a 10 hand pump bug sprayer. Half was applied to the entire pond surface each day to minimize spatial variance in enrichment. The amount of N added (0.294 mg m⁻²) was small compared to other nitrogen pools in the pond
   Quantities: 5 grams total 15N enriched ammonium chloride, 0.294 mg N m⁻², applied over 2 daysDuration: Applied on 3 June and 7 June 1999Conditions: Summer 1999, applied to pond surface
   Equipment: 10 hand pump bug sprayer, Isotech Inc. 15N enriched ammonium chloride (minimum 99% 15N)
2. Process specimens for isotope analysis
   All mayflies were frozen until analysis. The isotopic composition of individual mayflies (δ15N, expressed in parts per thousand) was determined using a PDZ Europa Hydra 20-20 mass spectrometer and a PDZ Europa ANCA-GSL elemental analyzer at the University of California Davis Stable Isotope Facility
   Quantities: Individual mayfly specimens analyzedDuration: Analysis performed after field seasonConditions: Laboratory conditions at UC Davis Stable Isotope Facility
   Equipment: PDZ Europa Hydra 20-20 mass spectrometer, PDZ Europa ANCA-GSL elemental analyzer
3. Classify specimens as marked or unmarked
   Individual mayflies were classified as marked or unmarked using a natural break in the distribution of δ15N values obtained from adults. A value of δ15N ≥ 5.0‰ was chosen as the minimum labeled value for adults; the maximum value of individuals classified as unlabeled was 4.67‰. Only 5.73% were reclassified when using δ15N = 4.5–5.0‰ as labeled

Typical Equipment

• 10 hand pump bug sprayer
• Isotech Inc. 15N enriched ammonium chloride
• PDZ Europa Hydra 20-20 mass spectrometer
• PDZ Europa ANCA-GSL elemental analyzer

Output Measurements

• δ15N isotopic composition
• marked vs unmarked classification

Papers Using This Protocol (1)

Species Studied With This Protocol