Amphibia-Reptilia (2013)
A quantitative analysis of the state of knowledge of turtles of the
United States and Canada
Jeffrey E. Lovich1,∗, Joshua R. Ennen1,2
Abstract. The “information age†ushered in an explosion of knowledge and access to knowledge that continues to
revolutionize society. Knowledge about turtles, as measured by number of published papers, has been growing at an
exponential rate since the early 1970s, a phenomenon mirrored in all scientific disciplines. Although knowledge about turtles,
as measured by number of citations for papers in scientific journals, has been growing rapidly, this taxonomic group remains
highly imperiled suggesting that knowledge is not always successfully translated into effective conservation of turtles. We
reviewed the body of literature on turtles of the United States and Canada and found that: 1) the number of citations is
biased toward large-bodied species, 2) the number of citations is biased toward wide-ranging species, and 3) conservation
status has little effect on the accumulation of knowledge for a species, especially after removing the effects of body size
or range size. The dispersion of knowledge, measured by Shannon Weiner diversity and evenness indices across species,
was identical from 1994 to 2009 suggesting that poorly studied species remained poorly-studied species while well-studied
species remained well studied. Several species listed as threatened or endangered under the U.S. Endangered Species Act
(e.g., Pseudemys alabamensis, Sternotherus depressus, and Graptemys oculifera) remain poorly studied with the estimated
number of citations for each ranging from only 13-24. The low number of citations for these species could best be explained
by their restricted distribution and/or their smaller size. Despite the exponential increase in knowledge of turtles in the United
States and Canada, no species of turtle listed under the Endangered Species Act has ever been delisted for reason of recovery.
Therefore, increased knowledge does not necessarily contribute appreciably to recovery of threatened turtles.
Keywords: Canada, conservation, Endangered Species Act, knowledge, literature, turtles, United States.
1 - U.S. Geological Survey, Southwest Biological Science
Center, 2255 North Gemini Drive, Flagstaff AZ 86001,
USA
2 - Present address: TN-SCORE, University of Tennessee,
Knoxville, Tennessee 37996, USA
∗Corresponding author; e-mail:
[email protected]
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A quantitative analysis of the state of knowledge of turtles of the
United States and Canada
Jeffrey E. Lovich1,∗, Joshua R. Ennen1,2
Abstract. The “information age†ushered in an explosion of knowledge and access to knowledge that continues to
revolutionize society. Knowledge about turtles, as measured by number of published papers, has been growing at an
exponential rate since the early 1970s, a phenomenon mirrored in all scientific disciplines. Although knowledge about turtles,
as measured by number of citations for papers in scientific journals, has been growing rapidly, this taxonomic group remains
highly imperiled suggesting that knowledge is not always successfully translated into effective conservation of turtles. We
reviewed the body of literature on turtles of the United States and Canada and found that: 1) the number of citations is
biased toward large-bodied species, 2) the number of citations is biased toward wide-ranging species, and 3) conservation
status has little effect on the accumulation of knowledge for a species, especially after removing the effects of body size
or range size. The dispersion of knowledge, measured by Shannon Weiner diversity and evenness indices across species,
was identical from 1994 to 2009 suggesting that poorly studied species remained poorly-studied species while well-studied
species remained well studied. Several species listed as threatened or endangered under the U.S. Endangered Species Act
(e.g., Pseudemys alabamensis, Sternotherus depressus, and Graptemys oculifera) remain poorly studied with the estimated
number of citations for each ranging from only 13-24. The low number of citations for these species could best be explained
by their restricted distribution and/or their smaller size. Despite the exponential increase in knowledge of turtles in the United
States and Canada, no species of turtle listed under the Endangered Species Act has ever been delisted for reason of recovery.
Therefore, increased knowledge does not necessarily contribute appreciably to recovery of threatened turtles.
Keywords: Canada, conservation, Endangered Species Act, knowledge, literature, turtles, United States.
1 - U.S. Geological Survey, Southwest Biological Science
Center, 2255 North Gemini Drive, Flagstaff AZ 86001,
USA
2 - Present address: TN-SCORE, University of Tennessee,
Knoxville, Tennessee 37996, USA
∗Corresponding author; e-mail:
[email protected]
To subscribe to Herp Digest, send a message to [email protected]. Wait for a confirmation message in your email. Simply Reply to the message (no text is necessary), and your address will be automatically added to the mailing list. To unsubscribe from this list, send a message to [email protected]. Reply to the confirmation message in your email (no text is necessary), and your address will be automatically removed.
