Name: using pharmacological manipulation and high-precision radio telemetry to study the spatial cognition in free-ranging animals
Uploaded: 2016-11-06T14:00:00
Description: Watch this Scientific Journal Video about Using Pharmacological Manipulation and High-precision Radio Telemetry to Study the Spatial Cognition in Free-ranging Animals at JoVE.com

This research was funded by Washington College's Provost's Office, Middendorf Fund, Hodson Trust, and Franklin and Marshall's Hackman Fund and College of Grants. We thank E. Counihan, S. Giordano, F. Rauh, and A. Roth for assistance in the field. We thank M. Conner, R. Fleegle, and D. Startt at Chesapeake Farms, and Chino Farms for permission and access. The Washington College GIS Program helped with the preparation of maps.

All procedures involving animal subjects were approved by the Institutional Animal Care and Use Committees of Franklin and Marshall and Washington Colleges and followed all local, state, and federal regulations.
1. Capture and Handling
<ol>
	<li>Place hoop traps in the target body of water that is known to contain turtles. Identify water depth ensuring that 4 - 5 inches of the trap remains above water to allow trapped turtles to surface and breathe. Be certain to expand and secure hoop traps to their maximum len...

<ol>
	<li>Shettleworth, S. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> Cognition, Evolution and Behavior. , (2010).</li><li>Bingman, V. P., Cheng, K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Mechanisms+of+animal+global+navigation:+comparative+perspectives+and+enduring+challenges.">Mechanisms of animal global navigation: comparative perspectives and enduring challenges.</a> Ethol. Ecol. Evol. 17, 295-318 (2005).</li><li>Mueller, T., O'Hara, R. B., Converse, S. J., Urbanek, R. P., Fagan, W. F. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Social+Learning+of+Migratory+Performance.">Social Learning of Migratory Performance.</a> Science. 341, 999-1002 (2013).</li><li>Putman, N. F., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=An+inherited+magnetic+map+guides+ocean+navigation+in+juvenile+Pacific+salmon.">An inherited magnetic map guides ocean navigation in juvenile Pacific salmon.</a> Curr. Biol. 24, 446-450 (2014).</li><li>Lohmann, K. J., Putman, N. F., Lohmann, C. M. F. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Geomagnetic+imprinting:+a+unifying+hypothesis+of+natal+homing+in+salmon+and+sea+turtles.">Geomagnetic imprinting: a unifying hypothesis of natal homing in salmon and sea turtles.</a> Proc. Natl. Acad. Sci., USA. 105, 19096-19101 (2008).</li><li>Fuxjager, M. J., Davidoff, K. R., Mangiamele, L. A., Lohmann, K. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+geomagnetic+environment+in+which+sea+turtle+eggs+incubate+affects+subsequent+magnetic+navigation+behaviour+of+hatchlings.">The geomagnetic environment in which sea turtle eggs incubate affects subsequent magnetic navigation behaviour of hatchlings.</a> Proc. R. Soc. B. 281, 1218-1225 (2014).</li><li>Shettleworth, S. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+evolution+of+comparative+cognition:+is+the+snark+still+a+boojum.">The evolution of comparative cognition: is the snark still a boojum.</a> Behav. Processes. 80, 210-217 (2009).</li><li>Fagan, W. F., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Spatial+memory+and+animal+movement.">Spatial memory and animal movement.</a> Ecol. Lett. 16, 1316-1329 (2013).</li><li>Collett, T. S., Graham, P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Insect+Navigation:+Do+Honeybees+Learn+to+Follow+Highways.">Insect Navigation: Do Honeybees Learn to Follow Highways.</a> Curr. Biol. 25, 240-242 (2015).</li><li>Menzel, R., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Honey+bees+navigate+according+to+a+map-like+spatial+memory.">Honey bees navigate according to a map-like spatial memory.</a> Proc. Natl. Acad. Sci., USA. 102, 3040-3045 (2005).</li><li>Roth, T. C., Krochmal, A. R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Pharmacological+Evidence+is+Consistent+with+a+Prominent+Role+of+Spatial+Memory+in+Complex+Navigation.">Pharmacological Evidence is Consistent with a Prominent Role of Spatial Memory in Complex Navigation.</a> Proc. R. Soc. B. 283, 20152548 (2016).</li><li>Roth, T. C., Krochmal, A. R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+role+of+age-specific+learning+and+experience+for+turtles+navigating+a+changing+landscape.">The role of age-specific learning and experience for turtles navigating a changing landscape.</a> Curr. Biol. 25, 333-337 (2015).</li><li>Krochmal, A. R., Roth, T. C., Rush, S., Wachter, K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Turtles+outsmart+rapid+environmental+change:+the+role+of+cognition+in+navigation.">Turtles outsmart rapid environmental change: the role of cognition in navigation.</a> Comm. Integr. Biol. , (2015).</li><li>Thorup, K., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Evidence+for+a+navigational+map+stretching+across+the+continental+U.S.+in+a+migratory+songbird.">Evidence for a navigational map stretching across the continental U.S. in a migratory songbird.</a> Proc. Natl. Acad. Sci., USA. 104, 18115-18119 (2007).</li><li>Lohmann, K. J., Lohmann, C. M. F., Putman, N. F. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Magnetic+maps+in+animals:+nature's+GPS.">Magnetic maps in animals: nature's GPS.</a> J. Exp. Biol. 210, 3697-3705 (2007).</li><li>Collett, M., Chittka, L., Collett, T. S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Spatial+Memory+in+Insect+Navigation.">Spatial Memory in Insect Navigation.</a> Curr. Biol. 23, 789-800 (2013).</li><li>Foden, W., Vi&#233;, J. C., Hilton-Taylor, C., Stuart, S. N., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Species+susceptibility+to+climate+change+impacts.">Species susceptibility to climate change impacts.</a> The 2008 Review of The IUCN Red List of Threatened Species. , (2008).</li><li>Kohler, E. C., Riters, L. V., Chaves, L., Bingman, V. P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+Muscarinic+Acetylcholine+Antagonist+Scopolamine+Impairs+Short-Distance+Homing+Pigeon+Navigation.">The Muscarinic Acetylcholine Antagonist Scopolamine Impairs Short-Distance Homing Pigeon Navigation.</a> Physiol. Behav. 60, 1057-1061 (1996).</li><li>Powers, A. S., Hogue, P., Lynch, C., Gattuso, B., Lissek, S., Nayal, C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Role+of+Acetylcholine+in+negative+patterning+in+turtles+(Chrysemys+picta).">Role of Acetylcholine in negative patterning in turtles (Chrysemys picta).</a> Behav. Neurosci. 123, 804-809 (2009).</li><li>Petrillo, M., Ritter, C. A., Powers, A. S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+role+for+Acetylcholine+in+spatial+memory+in+turtles.">A role for Acetylcholine in spatial memory in turtles.</a> Physiol. Behav. 56, 135-141 (1994).</li><li>Klinkenberg, I., Blokland, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+validity+of+scopolamine+as+a+pharmacological+model+for+cognitive+impairment:+A+review+of+animal+behavioral+studies.">The validity of scopolamine as a pharmacological model for cognitive impairment: A review of animal behavioral studies.</a> Neurosci. Biobehav. Rev. 34, 1307-1350 (2010).</li><li>Pradhan, S. N., Roth, T. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Comparative+behavioral+effects+of+several+anticholinergic+agents+in+rats.">Comparative behavioral effects of several anticholinergic agents in rats.</a> Psychopharm. (Berlin). 12, 358-366 (1968).</li><li>Harvey, J. A., Gormezano, I., Cool-Hauser, V. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Effects+of+scopolamine+and+methylscopolamine+on+classical+conditioning+of+the+rabbit+nictitating+membrane+response.">Effects of scopolamine and methylscopolamine on classical conditioning of the rabbit nictitating membrane response.</a> J. Pharmacol. Exp. Therap. 225, 42-49 (1983).</li><li>Evans, H. L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Scopolamine+effects+on+visual+discrimination:+modifications+related+to+stimulus+control.">Scopolamine effects on visual discrimination: modifications related to stimulus control.</a> J. Pharmacol. Exp. Therap. 195, 105-113 (1975).</li><li>Dreslik, M. J., Phillips, C. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Turtle+communities+in+the+upper+midwest,+USA.">Turtle communities in the upper midwest, USA.</a> J. Freshwater Ecol. 20, 149-164 (2005).</li><li>Sexton, O. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+method+of+estimating+the+age+of+painted+turtles+for+use+in+demographic+studies.">A method of estimating the age of painted turtles for use in demographic studies.</a> Ecology. 40, 716-718 (1959).</li><li>Wilson, D. S., Tracy, C. R., Tracy, C. R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Estimating+age+of+turtles+from+growth+rings:+a+critical+evaluation+of+the+technique.">Estimating age of turtles from growth rings: a critical evaluation of the technique.</a> Herpetologica. 59, 178-194 (2003).</li><li>Kenward, R. E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> A Manual for Wildlife Radio Tagging. , (2000).</li><li>Jones, D. N. C., Higgins, G. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Effect+of+scopolamine+on+visual+attention+in+rats.">Effect of scopolamine on visual attention in rats.</a> Psychopharm. 120, 142-149 (1995).</li><li>Araujo, J. A., Nobrega, J. N., Raymond, R., Milgram, N. W. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Aged+dogs+demonstrate+both+increased+sensitivity+to+scopolamine+impairment+and+decreased+muscarinic+receptor+density.">Aged dogs demonstrate both increased sensitivity to scopolamine impairment and decreased muscarinic receptor density.</a> Pharmacol. Biochem. Behav. 98, 203-209 (2011).</li><li>Greggor, A. L., Clayton, N. S., Phalan, B., Thornton, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Comparative+cognition+for+conservationists.">Comparative cognition for conservationists.</a> Trends Ecol. Evol. 29, 489-495 (2014).</li><li>Roth, T. C., Krochmal, A. R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Cognition-centered+conservation+as+a+means+of+advancing+integrative+animal+behavior.">Cognition-centered conservation as a means of advancing integrative animal behavior.</a> Curr. Opinion Behav. Sci. 6, 1-6 (2015).</li><li>LaDage, L. D., Roth, T. C., Cerjanic, A. C., Sinervo, B., Pravosudov, V. V. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Spatial+memory:+Are+lizards+really+deficient.">Spatial memory: Are lizards really deficient.</a> Biol. Lett. 8, 939-941 (2012).</li></ol>

The protocol presented here allows the experimenter to document and quantify the role of cognition in navigation. Manipulating cognition in the field has proven difficult, as most approaches leave experimenters unable to know which specific aspects of the animal&#39;s behavior are being manipulated. However, the protocol presented here allows the experimenter to accurately manipulate and thus assess the role of cognition in navigation. The technique further allows experimenters to monitor animal navigation in real-time w...

Cognition (herein defined as &#34;all processes involved in acquiring, storing, and using information from the environment&#34; 1) is central to an array of complex navigation tasks2. For example, Sandhill cranes (Grus canadensis) show a marked improvement in migratory precision with experience3, and sea turtle species imprint on their natal beaches as hatchlings and return as adults4-6. Similarly, successful migration, dispersal, and foraging hinge on an animal&#39;s ability to gather information about their spatial environment7,8. Some animals appear to learn navigational routes in relation to specific landscape features9 and may use spatial cognition when moving between nesting and foraging areas10. Recent work on Eastern Painted turtles (Chrysemys picta) suggests a critical period in navigation, where successful navigation of upland habitat as adults hinges on juvenile experience within a narrow age range (&#60; 4 years old11-13). Though together these studies demonstrate the progress that has been made in understanding the role of learning in navigation4-6, 14-16, the mechanisms that underlie such behaviors and the full role of cognition in navigation remain enigmatic, especially in vertebrates8, 17, 18.
Field investigations into the role of cognition in navigation are rare2, 8, 18, due largely to the methodological difficulties involved in monitoring, manipulating, and tracking wild animals. For example, the large spatial and temporal scales on which many animals navigate often preclude investigating both type of information that those animals potentially learn and how that information is acquired. Experimenters often face the logistical difficulties of detecting and locating animals when monitoring behavior over such large areas and time frames, thereby limiting the type of data that can be collected and the conclusions that can be drawn. Although the use of animal-mounted global positioning system (GPS) recorders may improve the probability of detection of widely ranging animals, spatial data collected by these means are generally of very coarse resolution and lack a detailed behavioral component. Consequently, the data that can be collected under such circumstances are of limited value for examining subtle variation in behavior among different groups or experimental treatments. Similarly, the direct, controlled manipulation of target behaviors is often prohibited by the spatial and temporal scales typical of navigation behaviors, as well as by inherent logistical constraints of field studies. Finding animals in their natural habitat, catching and manipulating them, and then collecting behavioral data without inadvertently producing spurious behaviors are major challenges of working with animals in the field. Therefore, the design of experiments on free-ranging animals is often constrained and the ability to conduct rigorous, controlled field experiments on the role of cognition in navigation is limited.
The present study circumvents many of the previous difficulties of investigating the relationship between cognition and navigation in the field by using a novel combination of pharmacological manipulation and high-resolution tracking of freely navigating animals under field conditions. Scopolamine, a muscarinic acetylcholine receptor (mAChR) antagonist, has been shown to block spatial memory formation and recall by blocking cholinergic activity in the brains of a variety of vertebrate taxa18-24. Scopolamine can be used effectively on free-ranging animals under field conditions11, 18 and has a marked but temporary effect (e.g., 6 - 8 hr in reptiles). Methylscopolamine, a mAChR antagonist that does not cross the blood-brain-barrier19-21, can be used to control for the possible peripheral effects of scopolamine and for non-cognitive aspects of behavior11. Pharmacology allows for the precise manipulation of cognition by directly affecting receptors, and high-precision radio telemetry allows for the observation of the resulting effects on behavior. Measurements taken via remote triangulation with both high spatial (&#177; 2.5 m) and temporal (15 min) resolution allow for the precise documentation and quantification of animal behavior relative to the experimental manipulation of cognition.
This study11 was conducted between May and August 2013 and 2014 at Chesapeake Farms, a 3,300 acre wildlife management and agriculture research area in Kent Co., MD, USA (39.194&#176;N, 76.187&#176;W). The protocol involves five main steps: (1) capturing and handling animals (2) affixing radio transmitters (3) preparing the pharmacological agents (4) monitoring and manipulating animal movements, and (5) analyzing spatial data. The study described herein focused on the Eastern painted turtle (Chrysemys picta). Turtles in the focal population engage in annual overland movements in which they leave their home ponds and navigate to alternative aquatic habitats using one of four very precise (&#177; 3.5 m), complex, and highly predictable routes11, 12. Pharmacological manipulation of animals in this system paired with high-resolution radio telemetry sheds light on the role of cognition in freely navigating wild animals.

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	<tbody>
		<tr height="22">
			<td height="22" style="height:22px;width:216px;">Scopolamine bromide</td>
			<td style="width:93px;">Sigma</td>
			<td style="width:119px;">S0929</td>
			<td style="width:167px;">USP</td>
		</tr>
		<tr height="43">
			<td height="43" style="height:43px;">Scopolamine methylbromide</td>
			<td>Sigma</td>
			<td>S8502, 1421009</td>
			<td style="width:167px;">USP and non USP versions</td>
		</tr>
		<tr height="43">
			<td height="43" style="height:43px;">Saline</td>
			<td>Hanna Pharmaceutical Supply Co., Inc.</td>
			<td>409488850</td>
			<td style="width:167px;">USP, formulated as an injectable&#160;</td>
		</tr>
		<tr height="22">
			<td height="22" style="height:22px;">Syringe filter</td>
			<td>Fisher</td>
			<td>09-720-004</td>
			<td style="width:167px;"></td>
		</tr>
		<tr height="22">
			<td height="22" style="height:22px;">Syringe</td>
			<td>Fisher</td>
			<td>14-823-30</td>
			<td style="width:167px;"></td>
		</tr>
		<tr height="22">
			<td height="22" style="height:22px;">Hypodermic needle</td>
			<td>Fisher</td>
			<td>14-823-13</td>
			<td style="width:167px;"></td>
		</tr>
		<tr height="85">
			<td height="85" style="height:85px;">Antenna</td>
			<td>Wildlife Materials</td>
			<td>3 Element Folding Yagi</td>
			<td style="width:167px;">Antennae with additional elements are available, but can be cumbersome in the field.&#160;</td>
		</tr>
		<tr height="43">
			<td height="43" style="height:43px;">Radio Receiver</td>
			<td>Wildlife Materials</td>
			<td>TRX-2000S</td>
			<td style="width:167px;">Water resistant models are also available.</td>
		</tr>
		<tr height="22">
			<td height="22" style="height:22px;">Compass</td>
			<td>Brunton&#160;</td>
			<td>Truarc 15</td>
			<td style="width:167px;"></td>
		</tr>
		<tr height="169">
			<td height="169" style="height:169px;">Radio transmitters</td>
			<td>Holohil Inc.</td>
			<td>BD-2, PD-2, RI-2B</td>
			<td style="width:167px;">Transmitter models vary in lifespan and signal output as a function of battery size and pulse rate settings, which can be customized based on the study question and organism.</td>
		</tr>
		<tr height="22">
			<td height="22" style="height:22px;">GPS</td>
			<td>Garmin</td>
			<td>eTrex Venture</td>
			<td style="width:167px;"></td>
		</tr>
		<tr height="43">
			<td height="43" style="height:43px;">Coaxial cable</td>
			<td>newegg.com</td>
			<td>C2G 40026</td>
			<td style="width:167px;">BNC connections are necessary.</td>
		</tr>
		<tr height="85">
			<td height="85" style="height:85px;">Hoop net</td>
			<td>Memphis Net and Twine&#160;</td>
			<td>TN325</td>
			<td style="width:167px;">Net mesh size should be chosen based on the minimum size of the target animal.&#160;</td>
		</tr>
	</tbody>
</table>

using pharmacological manipulation and high-precision radio telemetry to study the spatial cognition in free-ranging animals

An animal&#39;s ability to perceive and learn about its environment plays a key role in many behavioral processes, including navigation, migration, dispersal and foraging. However, the understanding of the role of cognition in the development of navigation strategies and the mechanisms underlying these strategies is limited by the methodological difficulties involved in monitoring, manipulating the cognition of, and tracking wild animals. This study describes a protocol for addressing the role of cognition in navigation that combines pharmacological manipulation of behavior with high-precision radio telemetry. The approach uses scopolamine, a muscarinic acetylcholine receptor antagonist, to manipulate cognitive spatial abilities. Treated animals are then monitored with high frequency and high spatial resolution via remote triangulation. This protocol was applied within a population of Eastern painted turtles (Chrysemys picta) that has inhabited seasonally ephemeral water sources for ~100 years, moving between far-off sources using precise (&#177; 3.5 m), complex (i.e., non-linear with high tortuosity that traverse multiple habitats), and predictable routes learned before 4 years of age. This study showed that the processes used by these turtles are consistent with spatial memory formation and recall. Together, these results are consistent with a role of spatial cognition in complex navigation and highlight the integration of ecological and pharmacological techniques in the study of cognition and navigation.

Using the above protocol, the role of cognition in navigation was assessed in a population of Eastern painted turtles (Chrysemys picta) that has experienced seasonal ephemeral water sources for ~100 years. This population inhabits a mix of ephemeral (drained annually and rapidly - in several hr) and permanent aquatic habitats (Figure 1). Previous studies suggest that after their ponds are drained, resident turtles navigate to alternative water sources with high p...

Watch this Scientific Journal Video about Using Pharmacological Manipulation and High-precision Radio Telemetry to Study the Spatial Cognition in Free-ranging Animals at JoVE.com

Using Pharmacological Manipulation and High-precision Radio Telemetry to Study the Spatial Cognition in Free-ranging Animals

This paper describes a novel protocol that combines the pharmacological manipulation of memory and radio telemetry to document and quantify the role of cognition in navigation.

An animal&#39;s ability to perceive and learn about its environment plays a key role in many behavioral processes, including navigation, migration, ...

The overall goal of this experiment is to determine the importance of spatial cognition in over land turtle navigation. This method can help answer key questions in ecology, including how animals respond to changes in their environment or navigate stressful landscapes and give us insight into the underlying cognitive and neurological processes. The main advantages of this technique are that animal movements are studied in a natural system with high spatial precision and behavior is manipulated using well studied pharmacological agents.Though this method can provide insight into the cognitive basis of animal movements, it can also be applied to other systems, such as conservation and neurobiology. To begin, locate a target body of water that is known to contain turtles. Identify a region within the site that has sufficient water depth to place traps.Deploy the hoop traps so that four to five inches will remain above water in order to give trapped turtles space to surface and breathe. Expand the traps to their maximum length. Stake the traps into place securely.Next, bait the traps with dead fish, chicken livers or necks, and a can of cat food or canned vegetables. Check the traps twice daily. Remove the turtles by holding the animal on the sides, avoiding contact with the claws or beak, which can cause injury.Place the turtle in a holding bag, attached to a spring scale and record the mass of the animal to the nearest gram. To affix the transmitter, first use a spatula and cloth to clear mud, debris, and algae from the attachment area. Swab this area, using 70%isopropanol.Use a small amount of five minute epoxy to attach the transmitter to the turtle carapace orienting it to ensure the transmitter has maximum contact with the shell. Position the antenna so that it trails behind the animal, parallel to the long axis of the body. Finally, cover the entire transmitter and approximately one centimeter of the surrounding carapace with five minute epoxy.After the epoxy is cured, usually overnight, return the turtle to the point of capture. To prepare the drug stocks, use an analytical balance in a fume hood to weigh enough scopolamine hydrobromide to make a one milligram per milliliter solution. Add the scopolamine to a conical tube containing the appropriate volume of injection saline.Vortex until dissolved. Next, weigh enough scopolamine methylbromide to make a one milligram per milliliter working solution. Add this to a conical tube containing the appropriate volume of injection saline.Vortex the solution until all powder is dissolved. Using a 0.22 micrometer pour syringe filter, transfer the scopolamine hydrobromide solution into a sterile sealed serum vial. Repeat the filtration process using a new syringe to filter the scopolamine methylbromide solution.Dial in the frequency of the target animal into the receiver. Using a Yagi antenna, and with the receiver gain set to medium, identify the general location of a tagged animal. Move to the general location of the target turtle, remaining at least 25 meters away.Using a GPS device, record the location. Identify the direction of the strongest signal. Turn the gain down as far as possible, while still receiving a detectable signal.Move the antenna to the left and record the bearing at which the signal is lost. This is the left knoll. Then repeat this process to determine the right knoll.These two knolls represent a single set of bearings. Next, move to a different location, ideally 60 to 90 degrees relative to the first bearing, if possible, and take the left and right knoll bearings again. A GPS location needs to be taken each time the tracker changes its position.Repeat this at different locations for a total of at least three, and up to five, bearing sets to increase the accuracy. Repeat the location collection every 10 to 15 minutes and record the bearing sets for the target animal. This will give movement data for the unmanipulated animals.Continue until the animal has navigated approximately half of its projected path. Then, proceed to the location of the animal and carefully recapture it. Using the mass collected previously, determine the correct dose of drug to administer for the specific animal collected.Swab the injection site with a 70%alcohol wipe. Using a one milliliter syringe with a 22 gauge needle, deliver the drug directly into the caudle peritoneal sinus. Release the animal as soon as possible at its site of capture.Track the movement of the animal using left and right knoll method until it reaches the projected destination. Using each pair of left and right knoll bearings, bisect the angle to find the resultant transmitter bearing. Repeat this for all bearings for a given time point, and triangulate to find the position of the animal at that time.This map shows the tracked movements of experienced adult turtles between temporary and permanent ponds. Despite maintaining high precision along traditional routes prior to injection, all adults in the test group deviated dramatically after receiving scopolamine treatment. This phenomenon was not seen in individuals treated with the control drug, methylscopolamine.Conversely, mapping of naive juveniles showed that even with scopolamine treatment, individuals maintained movement within traditional routes. This suggested that juvenile individuals with no previous experience at the site use local cues to navigate, whereas scopolamine treated adults use spatial memory to navigate, as they lost this ability when treated with scopolamine. This plot shows the movement of sample turtles prior to treatment.All treatment groups are seen to follow the traditional path with a high degree of accuracy. After treatment, adults in the scopolamine treatment group deviated significantly from the traditional path. All other groups continued to navigate with high precision.Once mastered, each set of bearings can be collected in no more than three minutes if tracking is performed properly. While attempting this procedure, it's important to remember to choose locations that are close enough to collect accurate data, but not too close to disturb the animal. After its development, this technique paved the way for researchers in the field of ecology and animal behavior to explore the neurological basis of cognition under natural conditions.

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Research

JoVE Journal

Environment

Determination of Microbial Extracellular Enzyme Activity in Waters, Soils, and Sediments using High Throughput Microplate Assays

Much of the nutrient cycling and carbon processing in natural environments occurs through the activity of extracellular enzymes released by microorganisms. Thus, measurement of the activity of these extracellular enzymes can give insights into the rates of ecosystem level processes, such as organic matter decomposition or nitrogen and phosphorus mineralization. Assays of extracellular enzyme activity in environmental samples typically involve exposing the samples to artificial colorimetric or fluorometric substrates and tracking the rate of substrate hydrolysis. Here we describe microplate based methods for these procedures that allow the analysis of large numbers of samples within a short time frame. Samples are allowed to react with artificial substrates within 96-well microplates or deep well microplate blocks, and enzyme activity is subsequently determined by absorption or fluorescence of the resulting end product using a typical microplate reader or fluorometer. Such high throughput procedures not only facilitate comparisons between spatially separate sites or ecosystems, but also substantially reduce the cost of such assays by reducing overall reagent volumes needed per sample.

Microplate based procedures are described for the colorimetric or fluorometric analysis of extracellular enzyme activity. These procedures allow for the rapid assay of such activity in large numbers of environmental samples within a manageable time frame.

Much of the nutrient cycling and carbon  processing in natural environments occurs through the activity of extracellular  enzymes released by ...

The Use of an Automated System (GreenFeed) to Monitor Enteric Methane and Carbon Dioxide Emissions from Ruminant Animals

Ruminant animals (domesticated or wild) emit methane (CH4) through enteric fermentation in their digestive tract and from decomposition of manure during storage. These processes are the major sources of greenhouse gas (GHG) emissions from animal production systems. Techniques for measuring enteric CH4 vary from direct measurements (respiration chambers, which are highly accurate, but with limited applicability) to various indirect methods (sniffers, laser technology, which are practical, but with variable accuracy). The sulfur hexafluoride (SF6)&#160;tracer gas method is commonly used to measure enteric CH4 production by animal scientists and more recently, application of an Automated Head-Chamber System (AHCS) (GreenFeed, C-Lock, Inc., Rapid City, SD), which is the focus of this experiment, has been growing. AHCS is an automated system to monitor CH4 and carbon dioxide (CO2) mass fluxes from the breath of ruminant animals. In a typical AHCS operation, small quantities of baiting feed are dispensed to individual animals to lure them to AHCS multiple times daily. As the animal visits AHCS, a fan system pulls air past the animal&#8217;s muzzle into an intake manifold, and through an air collection pipe where continuous airflow rates are measured. A sub-sample of air is pumped out of the pipe into non-dispersive infra-red sensors for continuous measurement of CH4 and CO2 concentrations. Field comparisons of AHCS to respiration chambers or SF6 have demonstrated that AHCS produces repeatable and accurate CH4 emission results, provided that animal visits to AHCS are sufficient so emission estimates are representative of the diurnal rhythm of rumen gas production. Here, we demonstrate the use of AHCS to measure CO2 and CH4 fluxes from dairy cows given a control diet or a diet supplemented with technical-grade cashew nut shell liquid.

The Use of an Automated System GreenFeed to Monitor Enteric Methane and Carbon Dioxide Emissions from Ruminant Animals

Accuracy and precision of the techniques used to measure methane emissions from ruminant animals are critically important for the success of greenhouse gas mitigation efforts. This manuscript describes the principles and operation of an automated system to monitor methane and carbon dioxide mass fluxes from the breath of ruminant animals.

Ruminant animals (domesticated or wild) emit methane (CH4) through enteric fermentation in their digestive tract and from decomposition of manure during ...

Empirical, Metagenomic, and Computational Techniques Illuminate the Mechanisms by which Fungicides Compromise Bee Health

Growers often use fungicide sprays during bloom to protect crops against disease, which exposes bees to fungicide residues. Although considered &#34;bee-safe,&#34; there is mounting evidence that fungicide residues in pollen are associated with bee declines (for both honey and bumble bee species). While the mechanisms remain relatively unknown, researchers have speculated that bee-microbe symbioses are involved. Microbes play a pivotal role in the preservation and/or processing of pollen, which serves as nutrition for larval bees. By altering the microbial community, it is likely that fungicides disrupt these microbe-mediated services, and thereby compromise bee health. This manuscript describes the protocols used to investigate the indirect mechanism(s) by which fungicides may be causing colony decline. Cage experiments exposing bees to fungicide-treated flowers have already provided the first evidence that fungicides cause profound colony losses in a native bumble bee (Bombus impatiens). Using field-relevant doses of fungicides, a series of experiments have been developed to provide a finer description of microbial community dynamics of fungicide-exposed pollen. Shifts in the structural composition of fungal and bacterial assemblages within the pollen microbiome are investigated by next-generation sequencing and metagenomic analysis. Experiments developed herein have been designed to provide a mechanistic understanding of how fungicides affect the microbiome of pollen-provisions. Ultimately, these findings should shed light on the indirect pathway through which fungicides may be causing colony declines.

Microbial consortia within bumble bee hives enrich and preserve pollen for bee larvae. Using next generation sequencing, along with laboratory and field-based experiments, this manuscript describes protocols used to test the hypothesis that fungicide residues alter the pollen microbiome, and colony demographics, ultimately leading to colony loss.

Growers often use fungicide sprays during bloom to protect crops against disease, which exposes bees to fungicide residues. Although considered ...

Ecosystem Fabrication (EcoFAB) Protocols for The Construction of Laboratory Ecosystems Designed to Study Plant-microbe Interactions

Beneficial plant-microbe interactions offer a sustainable biological solution with the potential to boost low-input food and bioenergy production. A better mechanistic understanding of these complex plant-microbe interactions will be crucial to improving plant production as well as performing basic ecological studies investigating plant-soil-microbe interactions. Here, a detailed description for ecosystem fabrication is presented, using widely available 3D printing technologies, to create controlled laboratory habitats (EcoFABs) for mechanistic studies of plant-microbe interactions within specific environmental conditions. Two sizes of EcoFABs are described that are suited for the investigation of microbial interactions with various plant species, including Arabidopsis thaliana, Brachypodium distachyon, and Panicum virgatum. These flow-through devices allow for controlled manipulation and sampling of root microbiomes, root chemistry as well as imaging of root morphology and microbial localization. This protocol includes the details for maintaining sterile conditions inside EcoFABs and mounting independent LED light systems onto EcoFABs. Detailed methods for addition of different forms of media, including soils, sand, and liquid growth media coupled to the characterization of these systems using imaging and metabolomics are described. Together, these systems enable dynamic and detailed investigation of plant and plant-microbial consortia including the manipulation of microbiome composition (including mutants), the monitoring of plant growth, root morphology, exudate composition, and microbial localization under controlled environmental conditions. We anticipate that these detailed protocols will serve as an important starting point for other researchers, ideally helping create standardized experimental systems for investigating plant-microbe interactions.

Ecosystem Fabrication EcoFAB Protocols for The Construction of Laboratory Ecosystems Designed to Study Plant-microbe Interactions

This article describes detailed protocols for ecosystem fabrication of devices (EcoFABs) that enable the studies of plants and plant-microbe interactions in highly controlled laboratory conditions.

Beneficial plant-microbe interactions offer a sustainable biological solution with the potential to boost low-input food and bioenergy production. A ...

Experimental Study of the Relationship Between Particle Size and Methane Sorption Capacity in Shale

The amount of adsorbed shale gas is a key parameter used in shale gas resource evaluation and target area selection, and it is also an important standard for evaluating the mining value of shale gas. Currently, studies on the correlation between particle size and methane adsorption are controversial. In this study, an isothermal adsorption apparatus, the gravimetric sorption analyzer, is used to test the adsorption capacity of different particle sizes in shale to determine the relationship between the particle size and the adsorption capacity of shale. Thegravimetric method requires fewer parameters and produces better results in terms of accuracy and consistency than methods like the volumetric method. Gravimetric measurements are performed in four steps: a blank measurement, preprocessing, a buoyancy measurement, and adsorption and desorption measurements. Gravimetric measurement is presently considered to be a more scientific and accurate method of measuring the amount of adsorption; however, it is time-consuming and requires a strict measuring technique. A Magnetic Suspension Balance (MSB) is the key to verify the accuracy and consistency of this method. Our results show that adsorption capacity and particle size are correlated, but not a linear correlation, and the adsorptions in particles sieved into 40 - 60 and 60 - 80 meshes tend to be larger. We propose that the maximum adsorption corresponding to the particle size is approximately 250 &#181;m (60 mesh) in the shale gas fracturing.

We use an isothermal adsorption apparatus, the gravimetric sorption analyzer, to test the adsorption capacity of different particle sizes of shale, in order to find out the relationship between particle size and the adsorption capacity of shale.

The amount of adsorbed shale gas is a key parameter used in shale gas resource evaluation and target area selection, and it is also an important standard ...

Measuring Stolons and Rhizomes of Turfgrasses Using a Digital Image Analysis System

Length and diameter of stolons or rhizomes are usually measured using simple rulers and calipers. This procedure is slow and laborious, so it is often used on a limited number of stolons or rhizomes. For this reason, these traits are limited in their use for morphological characterization of plants. The use of digital image analysis software technology may overcome measurement errors due to human mistakes, which tend to increase as the number and size of samples also increase. The protocol can be used for any kind of crop but is particularly suitable for forage or grasses, where plants are small and numerous. Turf samples consist of aboveground biomass and an upper soil layer to the depth of maximum rhizome development, depending on the species of interest. In studies, samples are washed from the soil, and stolons/rhizomes are cleaned by hand before analysis by digital image analysis software. The samples are further dried in a laboratory heating oven to measure dry weight; therefore, for each sample, the resultant data are total length, total dry weight, and average diameter. Scanned images can be corrected before analysis by excluding visible extraneous parts, such as remaining roots or leaves not removed with the cleaning process. Indeed, these fragments normally have much smaller diameters than stolons or rhizomes, so they can be easily excluded from analysis by fixing the minimum diameter below which objects are not considered. Stolon or rhizome density per unit area can then be calculated based on sample size. The advantage of this method is quick and efficient measurement of the length and average diameter of large sample numbers of stolons or rhizomes.

A software-based image analysis system provides an alternative method to study the morphology of stoloniferous and rhizomatous species. This protocol permits measurement of the length and diameter of stolons and rhizomes and can be applied to samples with a large amount of biomass and to a wide variety of species.

Length and diameter of stolons or rhizomes are usually measured using simple rulers and calipers. This procedure is slow and laborious, so it is often ...

Choice and No-Choice Bioassays to Study the Pupation Preference and Emergence Success of Ectropis grisescens

Many insects live above the ground as larvae and adults and as pupate below the ground. Compared to the above-ground stages of their life cycles, less attention has been paid on how environmental factors affect these insects when they pupate within the soil. The tea looper, Ectropis grisescens Warren (Lepidoptera: Geometridae), is a severe pest of tea plants and has caused huge economic losses in South China. The protocols described here aim to investigate, through multiple-choice bioassays, whether mature last-instar E. grisescens larvae can discriminate soil variables such as the substrate type and moisture content, and determine, through no-choice bioassays, the impact of the substrate type and moisture content on pupation behaviors and the emergence success of E. grisescens. The results would enhance the understanding of the pupation ecology of E. grisescens and may bring insights into soil-management tactics for suppressing E. grisescens populations. In addition, these bioassays can be modified to study the influences of various factors on the pupation behaviors and survivorship of soil-pupating pests.

Choice and No-Choice Bioassays to Study the Pupation Preference and Emergence Success of Ectropis grisescens

Here, we present a protocol to investigate the pupation preference of mature larvae of Ectropis grisescens in response to soil factors (e.g., substrate type and moisture content) using choice bioassays. We also present a protocol of no-choice bioassays to determine the factors that affect the pupation behaviors and survivorship of E. grisescens.

Many insects live above the ground as larvae and adults and as pupate below the ground. Compared to the above-ground stages of their life cycles, less ...

Long-term Video Tracking of Cohoused Aquatic Animals: A Case Study of the Daily Locomotor Activity of the Norway Lobster (Nephrops norvegicus)

We present a protocol related to a video-tracking technique based on the background subtraction and image thresholding that makes it possible to individually track cohoused animals. We tested the tracking routine with four cohoused Norway lobsters (Nephrops norvegicus) under light-darkness conditions for 5 days. The lobsters had been individually tagged. The experimental setup and the tracking techniques used are entirely based on the open source software. The comparison of the tracking output with a manual detection indicates that the lobsters were correctly detected 69% of the times. Among the correctly detected lobsters, their individual tags were correctly identified 89.5% of the times. Considering the frame rate used in the protocol and the movement rate of lobsters, the performance of the video tracking has a good quality, and the representative results support the validity of the protocol in producing valuable data for research needs (individual space occupancy or locomotor activity patterns). The protocol presented here can be easily customized and is, hence, transferable to other species where the individual tracking of specimens in a group can be valuable for answering research questions.

Long-term Video Tracking of Cohoused Aquatic Animals: A Case Study of the Daily Locomotor Activity of the Norway Lobster Nephrops norvegicus

Here we present a protocol to individually track animals over a long period of time. It uses computer vision methods to identify a set of manually constructed tags by using a group of lobsters as case study, simultaneously providing information on how to house, manipulate, and mark the lobsters.

We present a protocol related to a video-tracking technique based on the background subtraction and image thresholding that makes it possible to ...

Composition and Distribution Analysis of Bioaerosols Under Different Environmental Conditions

Variable microorganisms in particulate matter (PM) under different environmental conditions may have significant impacts on human health. In this study, we described a protocol for multiple analyses of the biological compositions in environmental PM. Five experiments are presented: (1) PM number monitoring by using a laser particle counter; (2) PM collection by using a cyclonic aerosol sampler; (3) PM collection by using a high-volume air sampler with filters; (4) culturable microbes collection by the Andersen six-stage sampler; and (5) detection of biological composition of environmental PM by bacterial 16SrDNA and fungal ITS region sequencing. We selected hazy days and a livestock farm as two typical examples of the application in this protocol. In this study, these two sampling methods, cyclonic aerosol sampler and filter sampler, showed different sampling efficiency. The cyclonic aerosol sampler performed much better in terms of collecting bacteria, while these two methods showed the same efficiency in collecting fungi. Filter samplers can work under low temperature conditions while cyclonic aerosol samplers have a sampling limitation for temperature. A solid impacting sampler, such as an Andersen six-stage sampler, can be used to sample bioaerosols directly into the culture medium, which increases the survival rate of culturable microorganisms. However, this method mainly relies on culture while more than 99% of microbes cannot be cultured. DNA extracted from the culturable bacteria collected by the Andersen six-stage sampler and samples collected by cyclonic aerosol sampler and filter sampler were detected by bacterial 16S rDNA and fungal ITS region sequencing.All the methods above may have wide application in many fields of study, such as environmental monitoring and airborne pathogen detection. From these results, we can conclude that these methods can be used under different conditions and may help other researchers further explore the health impacts of environmental bioaerosols.

Understanding the biological composition of environmental particulate matter is important for the study of its significant impacts on human health and disease spread. Here, we used three types of bioaerosol sampling methods and a biological analysis of airborne microbes to better explore airborne microbial communities under different environmental conditions.

Variable microorganisms in particulate matter (PM) under different environmental conditions may have significant impacts on human health. In this study, ...

Automated 3D Optical Coherence Tomography to Elucidate Biofilm Morphogenesis Over Large Spatial Scales

Biofilms are a most successful microbial lifestyle and prevail in a multitude of environmental and engineered settings. Understanding biofilm morphogenesis, that is the structural diversification of biofilms during community assembly, represents a remarkable challenge across spatial and temporal scales. Here, we present an automated biofilm imaging system based on optical coherence tomography (OCT). OCT is an emerging imaging technique in biofilm research. However, the amount of data that currently can be acquired and processed hampers the statistical inference of large scale patterns in biofilm morphology. The automated OCT imaging system allows covering large spatial and extended temporal scales of biofilm growth. It combines a commercially available OCT system with a robotic positioning platform and a suite of software solutions to control the positioning of the OCT scanning probe, as well as the acquisition and processing of 3D biofilm imaging datasets. This setup allows the in situ and non-invasive automated&#160;monitoring of biofilm development and may be further developed to couple OCT imaging with macrophotography and microsensor profiling.

Microbial biofilms form complex architectures at interphases and develop into highly scale-dependent spatial patterns. Here, we introduce an experimental system (hard- and software) for the automated acquisition of 3D optical coherence tomography (OCT) datasets. This toolset allows the non-invasive and multi-scale characterization of biofilm morphogenesis in space and time.