Paul Cryan, Ph.D.
Mysteries, underdogs, and gadgets have always fascinated me, so for the past two decades I have focused my research on using technology to reveal how some of the 43+ species of U.S. bats live their cryptic lives. My particular interests include uncovering bat migration behaviors and seasonal movements, discovering the details of their winter hideouts and survival strategies, and understanding how infectious diseases influence bat populations. What began as general interest in an understudied group of mammals has grown into a practical search for answers to two of the most pressing threats currently facing U.S. bats - fatalities at wind turbines and the emerging disease known as white-nose syndrome. My basic research approach is to start by synthesizing natural history and existing information, then test plausible new hypotheses in a scientifically defensible way through observational and experimental field studies. I gravitate toward new collaborations and technologies that take us beyond existing methods and expand our abilities to follow and discover what (and how) bats are doing out there in the dark.
- Ph.D. Biology, University of New Mexico, 2003
- M.S. Biology, University of New Mexico, 1997
- B.A. Biology, The Evergreen State College, 1991
- 2003 to present, Research Biologist, USGS Fort Collins Science Center, Fort Collins, CO
- 1999 to 2003, Student Trainee (SCEP), USGS Arid Lands Field Station (Fort Collins Science Center), Albuquerque, NM
- 1994 to 1997 & 1999 to 2002, Graduate Teaching Assistant, University of New Mexico, Albuquerque, NM
- 1998 to 1999, Wildlife Biologist, USGS Arid Lands Field Station (Fort Collins Science Center), Albuquerque, NM
- 1995 to 1997, Biological Science Technician, USGS Arid Lands Field Station (Fort Collins Science Center), Albuquerque, NM
Science and Products
Using sutures to attach miniature tracking tags to small bats for multimonth movement and behavioral studies
1. Determining the detailed movements of individual animals often requires them to carry tracking devices, but tracking broad-scale movement of small bats (< 30g) has been limited by transmitter technology and long-term attachment methods. This limitation inhibits our understanding of bat dispersal and migration, particularly in the context of...Castle, Kevin T.; Weller, Theodore J.; Cryan, Paul M.; Hein, Cris D.; Schirmacher, Michael R.
Optimizing conservation strategies for Mexican freetailed bats: a population viability and ecosystem services approach
Conservation planning can be challenging due to the need to balance biological concerns about population viability with social concerns about the benefits biodiversity provide to society, often while operating under a limited budget. Methods and tools that help prioritize conservation actions are critical for the management of at-risk species....Wiederholt, Ruscena; Lopez-Hoffman, Laura; Svancara, Colleen; McCracken, Gary; Thogmartin, Wayne E.; Diffendorfer, James E.; Mattson, Brady; Bagstad, Kenneth J.; Cryan, Paul; Amy Russell; Semmens, Darius J.; Rodrigo A. Medellín
White-nose syndrome initiates a cascade of physiologic disturbances in the hibernating bat host
Background The physiological effects of white-nose syndrome (WNS) in hibernating bats and ultimate causes of mortality from infection with Pseudogymnoascus (formerly Geomyces) destructans are not fully understood. Increased frequency of arousal from torpor described among hibernating bats with late-stage WNS is thought to...Verant, Michelle L.; Meteyer, Carol; Speakman, John R.; Cryan, Paul M.; Lorch, Jeffrey M.; Blehert, David S.
Watching the dark: New surveillance cameras are changing bat research
It is, according to an old proverb, “better to light a candle than to curse the darkness.” And those of us trying to discover new insights into the mysterious lives of bats often do a lot of cursing in the darkness. Bats do most things under cover of night, and often in places where humans and most other animals can’t go. This dark inaccessibility...Cryan, Paul M.; Gorresen, P. Marcos
Behavior of bats at wind turbines
Wind turbines are causing unprecedented numbers of bat fatalities. Many fatalities involve tree-roosting bats, but reasons for this higher susceptibility remain unknown. To better understand behaviors associated with risk, we monitored bats at three experimentally manipulated wind turbines in Indiana, United States, from July 29 to October 1, 2012...Cryan, Paul M.; Gorresen, P. Marcos; Hine, Cris D.; Schirmacher, Michael; Diehl, Robert H.; Huso, Manuela M.; Hayman, David T.S.; Fricker, Paul D.; Bonaccorso, Frank J.; Johnson, Douglas H.; Heist, Kevin W.; Dalton, David C.
Bat flight and zoonotic viruses
Bats are sources of high viral diversity and high-profile zoonotic viruses worldwide. Although apparently not pathogenic in their reservoir hosts, some viruses from bats severely affect other mammals, including humans. Examples include severe acute respiratory syndrome coronaviruses, Ebola and Marburg viruses, and Nipah and Hendra viruses. Factors...O'Shea, Thomas J.; Cryan, Paul M.; Cunningham, Andrew A.; Fooks, Anthony R.; Hayman, David T.S.; Luis, Angela D.; Peel, Alison J.; Plowright, Raina K.; Wood, James L.N.
Continental-scale, seasonal movements of a heterothermic migratory tree bat
Long-distance migration evolved independently in bats and unique migration behaviors are likely, but because of their cryptic lifestyles, many details remain unknown. North American hoary bats (Lasiurus cinereus cinereus) roost in trees year-round and probably migrate farther than any other bats, yet we still lack basic information about their...Cryan, Paul M.; Stricker, Craig A.; Wunder, Michael B.
Market forces and technological substitutes cause fluctuations in the value of bat pest-control services for cotton
Critics of the market-based, ecosystem services approach to biodiversity conservation worry that volatile market conditions and technological substitutes will diminish the value of ecosystem services and obviate the “economic benefits” arguments for conservation. To explore the effects of market forces and substitutes on service values, we...López-Hoffman, Laura; Wiederholt, Ruscena; Sansone, Chris; Bagstad, Kenneth J.; Cryan, Paul M.; Diffendorfer, James E.; Goldstein, Joshua; LaSharr, Kelsie; Loomis, John; McCracken, Gary; Medellin, Rodrigo A.; Russell, Amy; Semmens, Darius J.
Moving across the border: Modeling migratory bat populations
The migration of animals across long distances and between multiple habitats presents a major challenge for conservation. For the migratory Mexican free-tailed bat (Tadarida brasiliensis mexicana), these challenges include identifying and protecting migratory routes and critical roosts in two countries, the United States and Mexico. Knowledge and...Ruscena, Wiederholt; López-Hoffman, Laura; Cline, Jon; Medellin, Rodrigo; Cryan, Paul M.; Russell, Amy; McCracken, Gary; Diffendorfer, Jay; Semmens, Darius J.
Pathophysiology of white-nose syndrome in bats: a mechanistic model linking wing damage to mortality
White-nose syndrome is devastating North American bat populations but we lack basic information on disease mechanisms. Altered blood physiology owing to epidermal invasion by the fungal pathogen Geomyces destructans (Gd) has been hypothesized as a cause of disrupted torpor patterns of affected hibernating bats, leading to mortality. Here, we...Warnecke, Lisa; Turner, James M.; Bollinger, Trent K.; Misra, Vikram; Cryan, Paul M.; Blehert, David S.; Wibbelt, Gudrun; Willis, Craig K.R.
Roost selection by western long-eared myotis (Myotis evotis) in burned and unburned piñon–juniper woodlands of southwestern Colorado
All 16 species of bats known to occur in western Colorado are found at Mesa Verde National Park (MVNP) in the southwestern United States. Since 1996, wildfires have burned more than 70% of MVNP (> 15,000 ha), potentially altering food and roosting resources for bats. During the summers of 2006–2007, we investigated roost use by reproductive...Snider, E. Apple; Cryan, Paul M.; Wilson, Kenneth R.
Electrolyte depletion in white-nose syndrome bats
The emerging wildlife disease white-nose syndrome is causing widespread mortality in hibernating North American bats. White-nose syndrome occurs when the fungus Geomyces destructans infects the living skin of bats during hibernation, but links between infection and mortality are underexplored. We analyzed blood from hibernating bats and compared...Cryan, Paul M.; Meteyer, Carol Uphoff; Blehert, David S.; Lorch, Jeffrey M.; Reeder, DeeAnn M.; Turner, Gregory G.; Webb, Julie; Behr, Melissa; Verant, Michelle L.; Russell, Robin E.; Castle, Kevin T.