Within‐Ecosystem Comparison of Bigmouth Buffalo <i>Ictiobus cyprinellus</i> and Common Carp <i>Cyprinus carpio</i> Reveals Diverging Population Trajectories, Declining Recruitment, and a Lifespan of 148 Years
Bibliographic record
Abstract
ABSTRACT The bigmouth buffalo Ictiobus cyprinellus is a long‐lived, migratory freshwater fish native to North America whose numbers are declining amidst increasing conservation concerns. Recent studies have uncovered long lifespans, delayed maturation, and episodic recruitment of bigmouth buffalo. Building from previous work in the Qu'Appelle watershed of Saskatchewan, here we quantify otolith‐derived population demographics of bigmouth buffalo and invasive common carp Cyprinus carpio across multiple sites in the drainage. The common carp ( n = 125) and bigmouth buffalo ( n = 173) collected from 2018 to 2024 reveal that common carp reach asymptotic size two times faster, live three times shorter lives, and invest significantly more into reproduction while also exhibiting recruitment stability during the water control era (post‐1958). Indeed, invasive common carp now outnumber native bigmouth buffalo in this watershed by at least an order of magnitude. In contrast, only a single year class (1997) was evident for bigmouth buffalo after 1949. Therefore, only one recruitment year was evident for this species since common carp were first detected in the system in 1955. Remarkably, we find that as of 2024 more than 90% of bigmouth buffalo in this system are greater than 75 years old with a known maximum age of 148 years. We now know that the bigmouth buffalo is the 11th longest‐lived vertebrate out of more than 66,000 species, and across diverse systems can have recruitment gaps longer than any other animal. Bigmouth buffalo require immediate conservation reassessment amidst ongoing population declines.
Fetched live from OpenAlex and de-inverted. Abstracts are not stored in this database: the inverted indexes are 8.6 GB of the frame’s 9.3 GB of text, and the host has 13 GB free.
How this classification was reachedexpand
Full frame machine prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. The Gemma side is a direct model label for every work in the frame, read from the title-only record. The Codex side is a classifier learned from the 10,348 direct Codex labels and calibrated to design-weighted sample rates; fields without enough sample support carry no Codex call. Candidate is the union of the two sides; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels.
Distilled classifier scores by category (both heads)
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.000 | 0.000 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.001 | 0.001 |
| Science and technology studies | 0.001 | 0.000 |
| Scholarly communication | 0.001 | 0.001 |
| Open science | 0.000 | 0.001 |
| Research integrity | 0.000 | 0.000 |
| Insufficient payload (model declined to judge) | 0.002 | 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 source (direct Gemma or distilled Codex), 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".