Comparative Effectiveness of Three Techniques for Salamander and Gastropod Land Surveys

By McDade, Kirsten A.; Maguire, Chris C. | The American Midland Naturalist, April 2005 | Go to article overview

Comparative Effectiveness of Three Techniques for Salamander and Gastropod Land Surveys


McDade, Kirsten A., Maguire, Chris C., The American Midland Naturalist


ABSTRACT.-

We compared the effectiveness and efficiency of three terrestrial salamander and gastropod trapping techniques: pitfall traps, ground searches and cover boards. The study was conducted on 18 stands with three management histories in the Umpqua National Forest, southern Oregon Cascades. A total of 648 pitfall traps were open for 28 consecutive days in fall 1999. Two hundred twelve amphibians (eight species) and 202 gastropods (six species) were captured. Also in fall 1999, 36 h of ground searches covering 3600 m^sup 2^ resulted in the detection of 19 amphibians (two species) and 130 gastropods (six species). Four cover boards (100 × 100 cm) in stacks of two were placed in each stand and checked four times in fall 1999 and once in spring 2000 after snow melt. Cover boards concealed no amphibians and only two gastropods (one species). Pitfall traps were more efficient at capturing amphibians than ground searches (0.41 vs. 0.25 captures per hour of effort), but less efficient at capturing gastropods than ground searches (0.39 vs. 1.73 captures per hour of effort). Cover boards as used were ineffective at capturing either amphibians or gastropods. Climatic conditions of the southern Oregon Cascades likely influenced the results.

INTRODUCTION

In the Pacific Northwest, two methods commonly are used to sample terrestrial salamanders: pitfall trapping and ground searches. Cover boards, a third sampling method, have been used sparingly in the Northwest, despite their success in the eastern United States (DeGraaf and Yamasaki, 1992; Harpole and Haas, 1999; Monti et al., 2000; Hyde and Simons, 2001; Jaeger et al., 2001).

There are many pitfall trap variations, but generally a pitfall consists of a deep depression in the ground that entraps animals that fall into it and restricts their escape. Pitfall traps have been used to estimate the seasonal activity, reproductive status and abundance of species (e.g., Campbell and Christman, 1982; Corn and Bury, 1990). There is evidence, however, that estimates of salamander abundance derived from pitfall trapping are biased (Corn and Bury, 1991; Heyer et al., 1994, p. 75-141). Sub-surface activity, arboreal junkets (see Nussbaum et al., 1983, p. 11-25) and sedentary behavior all decrease the probability of capture. Consequently, trappability differs widely among species (Campbell and Christman, 1982; Bury and Corn, 1987; Corn and Bury, 1990).

Ground searches entail actively probing for salamanders on the forest floor within a defined area (area-constrained search), over a defined time period (time-constrained search) or a combination of both (time- and area-constrained search) (Welsh, 1987; Corn and Bury, 1990; Heyer et al., 1994, p. 75-109). Searches are performed during the night or day and vary in intensity from "low" to "high" depending on the amount of forest floor disruption (Heyer et al., 1994, p. 84-92). Ground searches provide information on salamander presence/absence and microhabitat use and they commonly are used for inventory purposes, e.g., as directed in the Survey and Management Provision of the Northwest Forest Plan (Corn and Bury, 1990; Oison, 1999). Similar to pitfall trapping, however, ground searches are inappropriate for abundance estimation because of possible search bias (Corn and Bury, 1990). Not only are salamanders difficult to detect in structurally complex environments, but detection efficiencies also may differ among investigators.

Cover boards are wooden boards of various dimensions that are placed on the forest floor to simulate natural down wood. Several studies have effectively used cover boards to capture salamanders (DeGraaf and Yamasaki, 1992; Davis, 1998; Harpole and Haas, 1999; Monti et al., 2000; Hyde and Simons, 2001; Jaeger et al., 2001). Because boards can be checked repeatedly without forest floor disruption and they require less effort to search than many natural forest floor objects, they have been proposed for long-term monitoring of terrestrial amphibian populations (Jung et al.

The rest of this article is only available to active members of Questia

Sign up now for a free, 1-day trial and receive full access to:

  • Questia's entire collection
  • Automatic bibliography creation
  • More helpful research tools like notes, citations, and highlights
  • Ad-free environment

Already a member? Log in now.

Notes for this article

Add a new note
If you are trying to select text to create highlights or citations, remember that you must now click or tap on the first word, and then click or tap on the last word.
One moment ...
Project items

Items saved from this article

This article has been saved
Highlights (0)
Some of your highlights are legacy items.

Highlights saved before July 30, 2012 will not be displayed on their respective source pages.

You can easily re-create the highlights by opening the book page or article, selecting the text, and clicking “Highlight.”

Citations (0)
Some of your citations are legacy items.

Any citation created before July 30, 2012 will labeled as a “Cited page.” New citations will be saved as cited passages, pages or articles.

We also added the ability to view new citations from your projects or the book or article where you created them.

Notes (0)
Bookmarks (0)

You have no saved items from this article

Project items include:
  • Saved book/article
  • Highlights
  • Quotes/citations
  • Notes
  • Bookmarks
Notes
Cite this article

Cited article

Style
Citations are available only to our active members.
Sign up now to cite pages or passages in MLA, APA and Chicago citation styles.

(Einhorn, 1992, p. 25)

(Einhorn 25)

1

1. Lois J. Einhorn, Abraham Lincoln, the Orator: Penetrating the Lincoln Legend (Westport, CT: Greenwood Press, 1992), 25, http://www.questia.com/read/27419298.

Cited article

Comparative Effectiveness of Three Techniques for Salamander and Gastropod Land Surveys
Settings

Settings

Typeface
Text size Smaller Larger
Search within

Search within this article

Look up

Look up a word

  • Dictionary
  • Thesaurus
Please submit a word or phrase above.
Print this page

Print this page

Why can't I print more than one page at a time?

Full screen

matching results for page

Cited passage

Style
Citations are available only to our active members.
Sign up now to cite pages or passages in MLA, APA and Chicago citation styles.

"Portraying himself as an honest, ordinary person helped Lincoln identify with his audiences." (Einhorn, 1992, p. 25).

"Portraying himself as an honest, ordinary person helped Lincoln identify with his audiences." (Einhorn 25)

"Portraying himself as an honest, ordinary person helped Lincoln identify with his audiences."1

1. Lois J. Einhorn, Abraham Lincoln, the Orator: Penetrating the Lincoln Legend (Westport, CT: Greenwood Press, 1992), 25, http://www.questia.com/read/27419298.

Cited passage

Welcome to the new Questia Reader

The Questia Reader has been updated to provide you with an even better online reading experience.  It is now 100% Responsive, which means you can read our books and articles on any sized device you wish.  All of your favorite tools like notes, highlights, and citations are still here, but the way you select text has been updated to be easier to use, especially on touchscreen devices.  Here's how:

1. Click or tap the first word you want to select.
2. Click or tap the last word you want to select.

OK, got it!

Thanks for trying Questia!

Please continue trying out our research tools, but please note, full functionality is available only to our active members.

Your work will be lost once you leave this Web page.

For full access in an ad-free environment, sign up now for a FREE, 1-day trial.

Already a member? Log in now.