Utility of vocal formant spacing for monitoring sandhill crane subspecies
Bibliographic record
Abstract
Abstract Three migratory subspecies of sandhill crane ( Grus canadensis ) occur in North America: greater ( G. c. tabida ), Canadian ( G. c. rowani ), and lesser ( G. c. canadensis ). These subspecies vary clinally in size from the large tabida to the small canadensis . All 3 subspecies co‐occur during the nonbreeding season, but field identification is challenging and census efforts typically do not even attempt to distinguish them. We developed a novel method to determine the subspecies composition of nonbreeding sandhill crane populations using formant spacing in vocalizations. Each note in a crane vocalization is comprised of several formants, or energy peaks in the frequency spectrum. Formant spacing is inversely proportional to the length of the sound‐emitting tube, or trachea. Analysis of formant‐spacing distributions for tabida and canadensis revealed that tabida has reduced formant spacing, as predicted based on its larger body size and correspondingly larger trachea. Comparisons of these subspecies‐specific formant‐spacing distributions to formant‐spacing distributions from calls recorded at 2 crane wintering areas in New Mexico, USA, showed that the wintering crane populations of the Middle Rio Grande Valley and the Lower Rio Grande Valley contain strikingly different proportions of the globally rare tabida (75.5% and 5.6%, respectively). These findings are concordant with crane subspecies composition estimates derived from hunter check stations in New Mexico. Formant‐spacing provides an indirect, noninvasive method of estimating body‐size distributions that has several practical advantages. We expect it to be most useful when body‐size classes have limited overlap, as is the case with New Mexico sandhill crane populations. © 2012 The Wildlife Society.
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How this classification was reachedexpand
Full frame distilled prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. Learned from the 10,348 direct Codex labels and 10,348 direct Gemma labels. Candidate is the union of thresholded teacher heads; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels or direct frontier model labels.
Codex and Gemma teacher scores by category
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.000 | 0.000 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.000 | 0.000 |
| Science and technology studies | 0.000 | 0.000 |
| Scholarly communication | 0.000 | 0.000 |
| Open science | 0.000 | 0.000 |
| Research integrity | 0.000 | 0.000 |
| Insufficient payload (model declined to judge) | 0.000 | 0.000 |
Machine scores (provisional)
The two teacher heads of the student model, read on this work. A score orders the frame for review; it never asserts a category, and the validation status ships verbatim with every row.
Baseline scores from an immature model (maturity gate not passed, 7 training rounds). Scores rank; they never assert a category.
score_only:v0-immature-baseline · verbatim from the scoring run: score_only means the number may rank works, and no category label ships from itClassification
machine, unvalidatedMachine predicted; a candidate call from one teacher head, not a consensus.
How this classification was reached, model by model and score by score, is at the end of the page under "How this classification was reached".