Where there’s smoke, there’s fire: Hypotheses for the high incidence of West Indian manatee calf strandings on the Brazilian semi-arid coast
Bibliographic record
Abstract
savannas, grasslands, and smaller mangrove systems linked to the shallow-water estuaries (Moro et al., 2015(Moro et al., , 2016)).This stretch of the coast is nearly straight and experiences significant wave energy.Its defining features include sandy beaches, sand dunes, and sandstone cliffs (Schaeffer-Novelli et al., 1990).In this region, most river systems are temporary, featuring hypersaline mangroves and meadows known as "apicuns" (Soares et al., 2021).Thus, mangroves are underdeveloped along this coastline due to insufficient freshwater runoff and extended periods of drought (Schaeffer-Novelli et al., 1990).An interesting characteristic of this region is the presence of submarine groundwater discharges in coastal waters (Meireles & dos Santos, 2012), where manatees go to drink freshwater (Alves, 2007) In this region, 84% of stranded manatees are calves, especially newborns, resulting in an 'inverted J-shape' age-specific mortality curve [Fig. 1, with data from Meirelles (2008), Silva (2010), Lima (2019), SIMBA (2021), SIMMAM (Cabral & Barreto, 2022), and Aquasis (unpublished)], while in the state of Paraíba, for example, 50% of stranded manatees were calves (Parente et al., 2004).Before 2013, manatee calves stranded on the semi-arid coast were sent to a rehabilitation facility in the state of PernambucoThe West Indian manatee is a threatened species, classified as 'Vulnerable' by the International Union for the Conservation of Nature's (IUCN) Red List of Threatened Species (Deutsch et al., 2008).In Brazil, the species faced intensive hunting in the past (Domning, 1982) and, presently, it is intentionally captured for human consumption and medicinal purposes (Barbosa, 2013;Luna et al., 2018).Additionally, various human activities negatively impact manatees in the country, including habitat loss, incidental capture in fishing nets, collision with boats, and pollution (see Meirelles et al., 2022 for a review).In northeastern Brazil, an unusually high incidence of calf strandings has been documented since the 1990's, particularly along a 400 km stretch between the states of Ceará and Rio Grande do Norte (Potiguar Basin), situated within a region known as the semi-arid coast (Parente et al., 2004;Meirelles, 2008;Silva, 2010;Balensiefer et al., 2017).Distinguished by its arid coastline, the semi-arid region harbors semi-deciduous forests,
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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 | 0.002 | 0.005 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.001 |
| Bibliometrics | 0.001 | 0.001 |
| Science and technology studies | 0.001 | 0.002 |
| Scholarly communication | 0.001 | 0.001 |
| Open science | 0.001 | 0.001 |
| Research integrity | 0.001 | 0.001 |
| Insufficient payload (model declined to judge) | 0.007 | 0.001 |
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".