CoChat
Sign Up
Cited by 192Amphibian and Reptile BiologyFreshwater macroinvertebrate diversity and ecologyEcology and Vegetation Dynamics Studies

The DOI matches its Crossref record; 39 of the 40 references it cites were found in a registry or an index.

Tests of Null Models for Amphibian Declines on a Tropical Mountain

Pounds, J. Alan, Fogden, Michael P. L., Savage, Jay M., Gorman, George C.·1997·Conservation Biology
DOI 10.1046/j.1523-1739.1997.95485.x
Open this paper in CoChat — free account

Abstract

Many of the recent, widespread declines and disappearances of amphibian populations have taken place in seemingly undisturbed, montane habitats. The question of whether the observed patterns differ from those expected from natural population dynamics is the subject of an ongoing controversy with important implications for conservation. We examined this issue for the Monteverde region of Costa Rica’s Cordillera de Tilarán, where a multi‐species population crash in 1987 led to the disappearance of the endemic golden toad ( Bufo periglenes) and many other species. Focusing on long‐term studies of other amphibian assemblages, we developed probabilistic null models for the number of disappearances. Tests of these models at Monteverde suggest that the patterns observed there are highly improbable in the context of normal demographic variability. Twenty species of frogs and toads (40% of the anuran fauna) were missing throughout our 1990–1994 surveys of a 30‐km 2 area. Not all organisms in this area had declined accordingly: the relative frequency of absences was much greater for anurans than for breeding birds. Nevertheless, anuran habitats, most of which are protected within the Monteverde Cloud Forest Preserve, seemed unchanged, and none of the breeding‐bird species known to be sensitive to deforestation was missing. Thus, only factors other than direct, obvious human impacts can explain the amphibian declines. Consistent with our tests of null models, analyses of recent population trends do not support the hypothesis that the 1987 crash was an extreme fluctuation from which populations are recovering. Surviving species for which baseline data are available—stream‐breeding glass frogs ( Hyalinobatrachium fleischmanni and Centrolenella prosoblepon) and a pond‐breeding treefrog ( Hyla pseudopuma)—remained far less abundant than they were before the crash and showed no increase during 1990‐1994. We documented an increase only for one terrestrial‐breeding rain frog ( Eleutherodactylus diastema). Pruebas de Modelos Nulos para Disminuciones de Anfibios en una Montaña Tropical Muchas de las disminuciones y desapariciones recientes de poblaciones de anfibios en varias partes del mundo se han producido en hábitats que aparentemente no han sido alterados. La pregunta de si los patrones observados difieren de lo que es predicho por la dinámica natural de poblaciones es el tema de una controversia actual que tiene consecuencias importantes para la conservación. Se examinó esta pregunta para la región de Monteverde en la Cordillera de Tilarán, Costa Rica, donde un colapso de poblaciones en 1987 produjo la desaparición del endémico sapo dorado ( Bufo periglenes) y muchas otras especies. Centrándose en estudios a largo plazo sobre anfibios de otras regiones, se desarrollaron modelos nulos probabilísticos con respecto al número de desapariciones. Al probarse estos modelos para Monteverde se sugiere que los patrones observados son poco probables dentro de los parámetros normales de la variabilidad demográfica. Durante 1990‐1994 en un área de 30‐km 2 , veinte especies de ranas y sapos (el 40% de los anuros de la región) estuvieron ausentes. No todos los organismos del área disminuyeron de la misma forma: por ejemplo, la frecuencia relativa de especies ausentes fue mucho mayor para los anuros que para las aves que se reproducen en el área de estudio. Sin embargo, la mayoría de los hábitats de anuros están protegidos dentro de la Reserva Biológica Bosque Nuboso de Monteverde, y no parecía que habían cambiado. Además, ninguna de las especies de aves que son afectadas de manera negativa por la deforestación estuvo ausente. Por lo tanto, las disminuciones de anfibios sólo pueden ser explicadas por factores que no son los impactos obvios y directos causados por los seres humanos. De acuerdo con nuestras pruebas de modelos nulos, los análisis de tendencias recientes de abundancia no apoyan la hipótesis de que el colapso de 1987 fuera una fluctuación extrema de la cual las poblaciones están recuperándose. Las especies sobrevivientes de las que existen datos demográficos anteriores al colapso—ranas de vidrio ( Hyalinobatrachium fleischmanni y Centrolenella prosoblepon), que se reproducen en quebradas, y una rana arborícola ( Hyla pseudopuma) que pone huevos en lagunas y pozos—eran mucho menos abundantes durante 1990–1994 de lo que fueron antes de este evento y no se encontró evidencias de aumento. Se documentó un incremento solo en las poblaciones de Eleutherodactylus diastema, que se reproduce en hábitats terrestres.

Overview

Integrity signals

Registry

Crossref · 10.1046/j.1523-1739.1997.95485.x

Cites

39 of 39 references verified0 citation errors · 0 not checkable

Statistics

Recomputing p-values needs the paper’s full text.

Verification

Claims the paper makes

This paper’s full text isn’t openly available, so its claims and self-check weren’t run. The registry and citation checks still apply.

Claims other papers make about this one

Each is checked against this paper’s own text: does it say what the citing paper says it does?

Citations

Cites

Show all 40 references

Research works printed but not linked: 11

  1. Blaustein A. R., 1994, Chicken Little or Nero’s fiddle? A perspective on declining amphibian populations, Herpetologica, 50, 85
  2. Hayes M. P. 1991. A study of clutch attendance in the Neotropical frog Centrolenella fleischmanni(Anura: Centrolenidae). Ph.D. dissertation University of Miami Coral Gables Florida.
  3. La Marca E., 1991, Population changes in Atelopus species of the Cordillera de Merida, Venezuela, Herpetological Review, 22, 125
  4. Pounds J. A., 1990, Disappearing gold, BBC Wildlife, 8, 812
  5. Pounds J. A., 1991, Amphibian watch: new clues in the case of the disappearing amphibians, Wildlife Conservation, 94, 16
  6. Pounds J. A. in press. Amphibians and reptiles. In N. M. Nadkarni and N. T. Wheelwright editors. The ecology and natural history of Monteverde Costa Rica: a background for conservation. Oxford University Press Oxford.
  7. Pounds J. A., 1996, Conservation of the golden toad: a brief history, Bulletin of the British Herpetological Society, 55, 5
  8. Savage J. M., 1966, An extraordinary new toad from Costa Rica, Revista de Biología Tropical, 14, 153
  9. Stiles F. G. and A. F. Skutch. 1989. Birds of Costa Rica. Cornell University Press Ithaca New York.
  10. Travis J., 1994, Calibrating our expectations in studying amphibian populations, Herpetologica, 50, 104
  11. Van Devender R. W., 1980, Preliminary checklist of the herpetofauna of Monteverde, Puntarenas province, Costa Rica and vicinity, Brenesia, 17, 319

Cited by

Sorted by citations

Related

See all

Metadata

Authors
Pounds, J. A., Fogden, M. P. L., Savage, J. M., & Gorman, G. C.
Affiliations
University of Miami (US)
ORCID
Savage, Jay M.
Venue
Conservation Biology
Publisher
Wiley
Published
1997-12-02
Volume
11
Issue
6
Pages
1307-1322
ISSN
  • 0888-8892 (ISSN-L)
  • 1523-1739
DOI
10.1046/j.1523-1739.1997.95485.x
OpenAlex
W2070659763
Cited by
192
References
40
Citations by year
2026: 1 · 2025: 2 · 2024: 1 · 2023: 3 · 2022: 4 · 2021: 5 · 2020: 8 · 2019: 4 · 2018: 4 · 2017: 7 · 2016: 5 · 2015: 7 · 2014: 5 · 2013: 9 · 2012: 7
FWCI
6.91
Type
journal article
Language
en
Open access
closed
Licence
onlinelibrary.wiley.com/termsAndConditions#vor (vor, 1920 d)
Locations
Conservation Biology (publishedVersion)
Topics
  • Life Sciences › Agricultural and Biological Sciences › Ecology, Evolution, Behavior and Systematics › Amphibian and Reptile Biology
  • Physical Sciences › Environmental Science › Ecology › Freshwater macroinvertebrate diversity and ecology
  • Physical Sciences › Environmental Science › Nature and Landscape Conservation › Ecology and Vegetation Dynamics Studies
Keywords
amphibian decline, null models, population collapse, Monteverde, cloud forest, amphibian assemblages, glassfrogs, Hyalinobatrachium fleischmanni, population trends

About these checks

Registry, retraction, Cites and statistics results are computed, not judged, with one exception: a printed reference that no index lists is read once by a model before it counts as a citation error. Claims are extracted by a model and kept only when their quote appears verbatim in the text; each cited source is then checked, with a model’s help, for whether it says what the claim relies on. Those verdicts can be wrong — read the claim’s quote and the cited source before relying on one.

Statistics and arithmetic are recomputed, not judged.

Confidence bands are shown only for fields calibrated on our annotated test set. None is calibrated yet, so no band is shown.

What counts as a claim ›How we measure confidence ›How we check this ›

Are you an author, or do you see a problem with this page? Request a review