Into the lion s den: Feeding behavior and territorial range of Pterois volitans on 3 reefs near El Porvenir, Guna Yala

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1 SIT Graduate Institute/SIT Study Abroad SIT Digital Collections Independent Study Project (ISP) Collection SIT Study Abroad Spring 2017 Into the lion s den: Feeding behavior and territorial range of Pterois volitans on 3 reefs near El Porvenir, Guna Yala Andrew Harwell SIT Study Abroad Follow this and additional works at: Part of the Environmental Health Commons, Latin American Studies Commons, Other Animal Sciences Commons, Terrestrial and Aquatic Ecology Commons, and the Zoology Commons Recommended Citation Harwell, Andrew, "Into the lion s den: Feeding behavior and territorial range of Pterois volitans on 3 reefs near El Porvenir, Guna Yala" (2017). Independent Study Project (ISP) Collection This Unpublished Paper is brought to you for free and open access by the SIT Study Abroad at SIT Digital Collections. It has been accepted for inclusion in Independent Study Project (ISP) Collection by an authorized administrator of SIT Digital Collections. For more information, please contact digitalcollections@sit.edu.

2 1 Into the lion s den: Feeding behavior and territorial range of Pterois volitans on 3 reefs near El Porvenir, Guna Yala Andrew Harwell University of North Texas School for International Training: Panamá, Spring 2017

3 2 Abstract Pterois volitans, or the red lionfish, is an invasive species that has proliferated throughout Atlantic and Caribbean waters of the Americas within the last 3 decades. Because of their numerous venomous spines, these fish face little predation on the reefs they colonize, and few fish in the Atlantic are equipped to eat them without consequence. This study aims to investigate the activity, den preference, territorial range, and feeding behavior of lionfish on 3 reefs around El Porvenir, Guna Yala. Since the only way to keep lionfish populations low is to remove them from the reef by hand, it is important to know when lionfish are active and where they will most likely be found. Furthermore, an understanding of P. volitans hunting range is vital for estimating the potential damage that a population can cause to a reef ecosystem. In this study, 8 lionfish were monitored for a total of 8 hours each over the course of 2 weeks. Throughout the observation period, den sites were marked and lionfish were identified by size. This information was later used to keep track of each lionfish s behavior and observe their hunting range. Lionfish moved an average of 2.52m away from their den sites while hunting on all reefs. The data from this research confirms existing studies which have shown that lionfish are primarily crepuscular and eat during dawn and dusk. This study also found that lionfish prefer to maintain dens, and that they typically do not travel far from these to hunt. The peak times for finding lionfish within their dens is 11am-12pm. They can, however, keep several dens, sometimes over great distances, and this expands their hunting radius far beyond their immediate territory. More research is needed to understand how this invasive species can spread throughout larger reefs.

4 3 Acknowledgements This challenging research would not have been possible without the support and expertise of many different people. The logistics of getting to El Porvenir and then to various reefs around the island were complicated, and my friends and I could not have done it without the help of Yari Jimenez and the Kuna people living on El Porvenir. Special thanks to Srs. Jason and Nestor for driving the boats and allowing us to use their kayak. I would also like to thank Chelsea Brown, Samuel Blake, Madeleine Gent, and Tara Verghis for letting me use their underwater cameras while conducting research. Also thanks to Jackson Podis and Eleah Caseau for moral support and for helping to make my time in Guna Yala unforgettable. Lastly, I d like to acknowledge Dr. Juan Maté for his valuable insight and Dr. Aly Dagang for her guidance throughout the entire SIT experience. Thanks also to Aly for her patience and lightheartedness while dealing with the logistics of moving 21 people all over the country. My time in Panamá has changed my perception of the world and my place in it for the better, and I will never forget the lessons I learned here. Thank you.

5 4 Table of Contents I. Abstract... 2 II. Acknowledgments... 3 III. Introduction... 5 IV. Research Question... 6 V. Methodology... 6 VI. Results VII. Discussion VIII. Conclusion IX. Works cited... 21

6 5 Introduction P. volitans, or the common red lionfish, is a venomous reef fish of the family scorpaenidae, which are mostly slow-moving and equipped with venomous spines. The red lionfish is native to Indo-Pacific waters, where it is kept in check by local predators and competition for food resources (Sandel, 2008). It is unknown exactly how these Pacific-based fish were introduced to Atlantic reefs, but the current theory is that a lionfish aquarium in Florida was accidentally emptied into the bay during Hurricane Andrew (Albins, 2008). These four or five fish proceeded to lay millions of eggs and the population increased sharply thereafter. With so many challenges already facing Caribbean reef ecosystems from climate change, nitrate pollution, and overfishing, the lionfish explosion is an unwelcome burden, and eradication has proved incredibly difficult (Sandel, 2008). It is imperative to understand the ecology of P. volitans to develop strategies that minimize its impact on reef ecosystems. The Pacific red lionfish, or Pterois volitans, has invaded numerous reefs along the Atlantic coast of the Americas over the last two decades, decimating important fish populations along the way (Albins, 2008). Lionfish pose a serious threat to Atlantic reef ecosystems for several reasons. The most obvious of these is that lionfish have venomous spines on their fins and face little predation in the reefs they invade. Their venom is so toxic that few fish can eat them without dying, and they can inflict painful stings on humans as well (Manso et al., 2015). Lionfish themselves are voracious predators, with adults consuming an average of 8.5g of biomass per day (Albins, 2008). They primarily feed on small fish and crustaceans, which cuts into the food supply of larger, more economically important fish such as grouper and sea bass (Morris, 2009). Some of the fish they consume are important grazers which help to maintain the balance of algae on top of the coral. The decrease in grazing fish ultimately leads to an unhealthy proliferation of algae, blocking sunlight from reaching the zooxanthellae of the coral (Albins, 2008). Lionfish reproduction is rapid and exponential. Each female lionfish can lay up to 2 million eggs per year, leading to huge population booms (Sandel et al., 2015). These fish are the perfect storm to western Atlantic reefs, and they have reproduced so quickly that governments and organizations have had little time to implement anti-lionfish practices. Lionfish are incredibly hard to catch by hand because they often congregate at depths of 100 meters, far out of the reach of SCUBA divers (Lesser, 2011). Experimental efforts to use one lionfish predator, grouper, to reduce populations have proven moderately successful, but grouper have unfortunately been overfished in the Western Atlantic (Mumby et al., 2011). Lionfish tend to live at depths from m, and they prefer to hide in rugose, convoluted reef structures where they are better camouflaged (Bejarano et al., 2015). When they are feeding, they extend their fins outward and use them to corner small-bodied fish and crustaceans, sometimes recruiting fellow lionfish to attack entire shoals (Green et al., 2011). This behavior has led to enormous decreases in recruitment of native fishes to coral habitats (Green et al., 2012). Lionfish have been shown to be crepuscular feeders in the Atlantic, meaning that they eat during twilight hours and rest throughout midday (Green et al., 2011).

7 6 What is ultimately needed to help control lionfish populations is demand from consumers. While lionfish do have venomous spines, the meat itself is both safe to eat and nutritious (Morris, 2011). Because all of the venom is localized as mucous around the spines, an experienced chef needs only to remove the fins and head to render the meat harmless. Some organizations, including ClearThisFish.org and others, have taken it upon themselves to hunt lionfish and even host competitions. This has helped to spread awareness about the effects of lionfish on coral reefs, but it is still not enough to keep populations low. As most lionfish fishing requires spearfishing, there is not enough supply to meet what little demand there is. There are currently projects being developed by NOAA to build lionfish traps which could be used to catch the fish en masse and at greater depths than those accessible by divers (Gittings, 2017). If the public becomes more informed about the hazards lionfish pose to the environment, and if fishermen can find a way to make a profit on lionfish sales, then there is hope of lessening the impact of these invasive fish on coral reefs. This study will be conducted off the coast of El Porvenir, a small island close to Wichub Wala in the Gulf of Guna Yala. There are many pristine reefs near the island, and the calm, clear waters of the gulf make it ideal for snorkeling and freediving. Most of these reefs are shallow enough to do behavioral studies of fish without the use of SCUBA, so minimal equipment is needed to conduct observational research. While P. volitans normally lives at depths >10m, the reefs around El Porvenir are full of the rocky outcroppings and drop-offs that it prefers, making it possible to monitor them from shallower depths (Bejarano et al., 2015). The time of study will be from April 17 th to May 2 nd, just prior to the wet season in Panama. There is little research available about lionfish den-keeping or hunting range. The aim of this observational study is to investigate the ecology of lionfish by filming them on 3 reefs around El Porvenir. This information can be used to determine if P. volitans maintains territorial dens, and if so, how far from these dens the fish travel. In addition, this study aims to confirm activity and peak feeding times for all lionfish observed. Some behavioral studies have already been conducted with lionfish, but none in the Guna Yala area. Research Question Do red lionfish maintain territorial dens around El Porvenir, Guna Yala, and if so, how far and at what time do they travel from these to hunt? Methodology The first phase of this research involved scouting 3 reefs around El Porvenir to confirm the presence of lionfish. Previous research has shown that lionfish prefer rugose and convoluted reef structures (Bejarano et al., 2015), so scouting required snorkeling around these habitats until a lionfish was found. In most cases, the lionfish could only be spotted by its fins from above, and proper identification necessitated diving down to examine rocky outcroppings and caves.

8 7 Whenever a lionfish was found, the site of its den was marked using GPS and flagging tape (Figure 1). Figure 1: Map of coral reefs around El Porvenir. Den sites are marked as Reef #1, 2, and 3, with GPS coordinates corresponding to each. Measuring tape was used to measure the size of each individual lionfish as well as log the depth and size of the dens. Lionfish were then named for ease in note-taking, using their size as a general method of identification. Without proper tagging, it is impossible to know if the lionfish monitored were the same from day to day, but the fact that these fish remained in the same dens and were the same exact size was enough evidence to guess their identity. In total, 8 lionfish were found, measured, and named (Table 1). Table 1: Names, lengths, and den details of each lionfish monitored in the study. Name Length Den Substrate Depth Den length GPS Reef Abdiel 15cm rock/dead coral.5m.6m 9 33'27"N, 78 56'48"W 1 Esme 9cm rock/dead coral.5m.6m 9 33'27"N, 78 56'48"W 1 Joey 15cm lettuce coral 2.4m.5m 9 33'27"N, 78 56'45"W 2 Lionel 12cm lettuce coral 3m.75m 9 33'27"N, 78 56'45"W 2 Lolita 14cm lettuce coral 5m 1.1m 9 33'52"N, 78 57'07"W 3 Marta 10cm lettuce coral 2.4m.5m 9 33'27"N, 78 56'45"W 2 Rosa 10cm rock/dead coral.5m.6m 9 33'27"N, 78 56'48"W 1 Bruno 16cm lettuce coral 5m 1.1m 9 33'52"N, 78 57'07"W 3

9 8 Three days of scouting were required to find the lionfish and to confirm that the sites chosen were in fact dens and not transient resting places. All reefs monitored in this study were of different sizes, as seen in Figure 1. Reef #1 was a rocky structure created by coral mining and offered numerous crevices for fish to hide in (Figure 2). This reef was only 10-20m in diameter and was only a few meters away from El Porvenir. Reef #2 was further out to sea than Reef #1 and provided much deeper reefs. This reef consisted mainly of lettuce and fire coral, and provided caves and outcroppings at depths of 3-8m (Figure 3). Reef #3 was much patchier than Reef #2 and dropped off to depths of 10+ meters and consisted mainly of lettuce coral islands surrounded by sediment (Figure 4). The reef sites used in this study were chosen because each was separated by seagrass and sand, making them effectively cut off from one another. Figure 2: Den space found in Reef #1. Notice the rocky outcropping and lack of coral. Abdiel, Rosa, and Esme all lived in this same den.

10 9 Figure 3: Example of den space on Reef #2. The fins of Lionel can be seen jutting out of a space in the right-hand corner. This reef was covered in lettuce and fire coral which provided innumerable caves and overhangs. Figure 4: Bruno and Lolita hunting near den space on Reef #3. This den was made up of lettuce coral and was surrounded by sand and sediment.

11 10 During the observation phase, each lionfish was watched and filmed at a distance of 1-2 meters, with notes taken every time a fish changed behavior. Activity was grouped into 3 categories: Hunting, which includes hovering, stalking prey, and eating, moving, which involves the lionfish swimming from one area to another, and resting, which involves the lionfish hiding in the reef with spines and fins laid flat (Green et al., 2011). Video was recorded anytime a lionfish changed behavior as well. In addition to this, measuring tape was attached to the original den site and then used to measure total distance traveled by each lionfish. Measurements were also recorded when a lionfish was found in a new den site, as was sometimes the case. Video was taken during the 3 rd block of time of all lionfish feeding strikes, along with what type of prey they were hunting. Once the lionfish dens were marked and the fish themselves were assigned names and descriptions, they were observed at different times of day to determine their hunting and resting habits. This process involved snorkeling above the dens and watching the lionfish for 1½ hour blocks of time at dawn, midday, and dusk (Table 2). In order to account for all reefs, a rotating schedule was used. After the first two blocks were completed, the third block was reserved entirely for monitoring the lionfish at their peak feeding times to observe their hunting behavior. By the end of observation, each lionfish had been monitored for approximately 8 hours, with some gaps due to unexplained absences. Table 2: Blocks of time consisting of 1½ hours and 2 hours were used to observe the lionfish. These were alternated for each reef to ensure all lionfish were observed at the same hours. Dawn Midday Dusk Block 1 6:00-7:30am 11am-12:30pm 3-4:30pm Block 2 7:00-8:30am 12-1:30pm 4-5:30pm Block 3 (feeding time) 6:30-8:30am n/a 4:30-6:30pm After all lionfish had been monitored and all time and distance measurements had been recorded, the data was entered in Microsoft Excel for analysis. Lionfish hunting behaviors were entered as a series of data points, with each five-minute block corresponding to one behavior (hunting, moving, resting). This was then used to calculate the total amount of time spent on each behavior, for each lionfish, for each block of time, and for each reef. Averages were then calculated by combining all time spent on each behavior for all lionfish. From these averages, percentages could be calculated for how each lionfish spent a particular block of time. In addition to creating an activity map, MS Excel was also used to analyze distance traveled from the den to generate a hunting radius for each lionfish. Raw data was entered into a spreadsheet and then averages were taken for the distances traveled away from the den, either for hunting or for finding a new den site. These averages were then used to generate a box and

12 11 whisker plot which reflects the hunting radius of all lionfish at dawn, midday, and dusk. The same was repeated for the individual reefs to show how far lionfish traveled on a given reef. Due to the presence of outliers, another box and whisker plot was generated without the use of averages to account for the fact that some lionfish moved great distances over the reef. As this was an observational study, much of the data was qualitative rather than quantitative. Analysis often involved poring over video footage to find examples of hunting, resting, and moving behaviors to correlate with the numerical data. All cases of lionfish feeding on other fish were noted, and a Reef Fish Identification Book was used to identify which fish were preyed upon (Humann, 2014). Results The results of this data indicate that lionfish spend the majority of their time near their den sites, such that it is possible to predict with some certainty where they will be. In this case, the lionfish spent an average of 414 out of 780 minutes of observation time within 1m of the marked den. This equates to a 53.1%% chance of finding the lionfish near the den at any given time. The other times, the lionfish was either completely absent from the den or was hunting at a distance farther than 1m. This information was also used to calculate percentages for the likelihood of finding a lionfish near the den for 30 minute intervals (Figure 5) % 90.00% 80.00% 70.00% 60.00% 50.00% 40.00% 30.00% 20.00% 10.00% 0.00% Probability of finding lionfish within 1m of den Figure 5: Graph showing the probability of finding a lionfish within 1m of den at 30 minute intervals

13 12 Lionfish were monitored at three different blocks of time and their behavior was recorded as hunting, resting, or moving. Any time where a lionfish was absent was excluded from the data. Averages of all times spent on different behaviors were calculated and used to generate a percentage and activity profile for each block of time (Table 2, Figure 6). Table 2: Average times spent on hunting, moving, and resting for all lionfish, as recorded for dawn, midday, and dusk. Hunting Moving Resting 6-8:30am 149.5±47.5 min 3.8±4.7 min 75.5±43.4 min 11am-1:30pm 4.4±11.6 min.6±1.6 min 163.6±30.2 min 3-5:30pm 139.9±91.5 min 2.9±3.2 min 97.3±54.0 min Lionfish Activity Profile % 90.00% 80.00% 70.00% 60.00% 50.00% 40.00% 30.00% 20.00% 10.00% 0.00% 6-8:30am 11am-1:30pm 3-5:30pm Hunting Resting Moving Figure 6: This graph shows the average percentage of time spent on each activity for dawn, midday, and dusk. All distances traveled away from the lionfish s den were measured in meters using a measuring tape. The average hunting radii for Reef #1 was 5.49±4.62m, for Reef #2 the range was 8.41±9.62m, and for Reef #3 the range was 1.76±2.75 (p=0.534) (Figure 7). The average hunting radius for the time from 6:00-8:30am was 3.39±3.24m, from 11am-1:30pm was 1.23±1.36m, and from 3-5:30pm was 3.06±3.84m (p=0.309) (Figure 8). The wide range and outliers among the reef data has been shown in the third graph to include the fact that some lionfish traveled great distances across the reef (Figure 9).

14 13 Figure 7: Average lionfish hunting range by reef. Bars denote minimums and maximums, lines indicate the median, and dots indicate outliers Figure 8: Average lionfish hunting range by time of day. Bars denote minimums and maximums, lines indicate the median, and dots indicate outliers

15 14 Figure 9: Lionfish hunting range by reef. Bars denote minimums and maximums, lines indicate the median, and dots indicate outliers Several interesting behaviors were observed while filming the lionfish during hunting hours. The first of these was that Esme, the smallest fish on Reef #1, preyed solely upon benthic animals, namely dash gobies (Figure 10). While hunting, Esme would hover above the gobies them for several seconds, blowing air into the sediment to stir up the animal before striking. Another lionfish, Rosa, primarily hunted sharp-nosed pufferfish (Figure 11). These small fish seem to be unafraid of lionfish, and will curiously hover around them and even nip at their fins. Hunting in this case involved the lionfish waiting around until a pufferfish swam close to its mouth, and then sucking it in with powerful jaw muscles. There were several instances where Rosa would corner a fish into a crevice with her fins and then strike. These behaviors, the stirring up of benthos and the cornering of fish, were previously observed by Morris et al. (2009). On Reefs #2 and #3, the lionfish could be observed solely hunting juvenile three-spot damselfish, which have a characteristic black marking on their dorsal fins (Figure 12). These damselfish inhabit spaces in lettuce coral, and they frequently dart out to graze on algae and maintain their gardens. The lionfish would adopt a vertical posture over the lettuce coral where these damselfish lived, and would stalk them every time they left the safety of the coral. In all cases, lionfish were shown to be slow-moving suction feeders, feeding opportunistically on any fish that was small enough or close enough to be eaten.

16 15 Figure 10: Dash goby sitting atop the benthos. Figure 11: Sharp-nosed pufferfish approaching lionfish prior to strike

17 16 Figure 12: Damselfish hiding from lionfish in lettuce coral just after strike Discussion The results of this research indicate that lionfish do maintain territorial den spaces within the coral. They often use these to rest and take shelter when the current is particularly strong. The data also show that lionfish are more active during crepuscular hours (Green, 2011), and that they exhibit a hunting range that extends well beyond their den site. The lionfish also exhibited interesting hunting behaviors which were documented on film. This study showed that lionfish do maintain dens around the reef. They are not nomadic (Morris, 2009), and they spend much of the day resting upside down in outcroppings and caves made by rock and coral. Because of their long spines, lionfish are not particularly strong swimmers and are easily buffeted by the current. On particularly windy days, lionfish were usually found within their den spaces where they did not have to fight the waves. Den spaces were almost always shared by 2-3 lionfish, except in the case of Lionel, who was solitary throughout the study. Research suggests that males compete with one another for mating partners, and that one male can live alongside multiple females in the same area (Ruiz, 2006). Thus, dens may also be used by males as protection and for housing other females. This is useful information for divers who may be hunting or conducting research, as there is a high likelihood that a lionfish can be found near the same den over the course of multiple days. Figure 6 shows that the most likely time to find a lionfish in its den is from 11am-12pm. The lionfish in this study were shown to be crepuscular and could be found hunting at sunrise and sunset. This confirms previous research by Green et al. (2011), who hypothesized that the crepuscular feeding habits were due to an availability of prey. This appeared to be the case in the reefs monitored in this study, as other fish were much more active at crepuscular hours as well. In addition to this, the low-light conditions at dawn and dusk give the lionfish a better chance of avoiding detection by both predators and prey while still allowing them to take

18 17 advantage of their good eyesight (Green et al., 2011). In this study, lionfish observed in the morning were somewhat more active than lionfish studied in the evening. Based on this study, the best time for spearfishermen to hunt lionfish is from 6-7:30am and 5-6:30am, when they are the most conspicuous and closest to their den sites. While the lionfish did maintain dens around El Porvenir, they frequently left these to hunt for prey during crepuscular hours. They were not shown to be ambush predators, as they often searched for and stalked prey throughout the coral. In most cases, the lionfish stayed within a 1-3m radius of their den space to hunt, and they occasionally returned to the den to take short breaks. This prevented them from expending energy to fight the current. The short hunting radius around the immediate den could be explained by the fact that there was an abundance of prey in the immediate area. Other fish were not wary of the lionfish, and sharp-nosed pufferfish and damselfish often swam very close. In a few instances these were snapped at or eaten by the lionfish, so it appears that prey have not adapted to the presence of this new predator on the reef. The data collected in this study closely resemble the data collected by Green et al. (2011), who monitored total distance traveled by lionfish at dawn and dusk rather than hunting radius. Throughout the study, all lionfish were followed with a camera and video was taken when a lionfish changed its behavior. The behaviors noted were hunting, resting, and moving. Hunting involved a characteristic hovering motion, where the lionfish outstretched its venomous spines and floated effortlessly above the substrate (Figure 13). In this position, the lionfish searched for prey among the coral and benthos, switching to a more vertical stalking posture when a target was found. Resting involved floating upside down within the den, a posture facilitated by swim bladder muscles (Figure 14). Moving lionfish were in transit from one section of the reef to another and were not concerned with hunting prey. One unexpected finding in this study was that while lionfish do maintain territorial dens, they do not always inhabit the same den. There were a few occasions during the observation period where a lionfish would go missing, or would be found a great distance away in another coral overhang. When observed the next day, the lionfish would maintain the same short hunting radius around the new den. One lionfish, Marta, was observed swimming over 30m from one den site to another on Reef #2. This indicates that lionfish may migrate throughout the reef, and that their hunting territory is much larger than the area around a single den. In some cases, when a lionfish would move out, a new animal would move in as was the case on Reef #3 (Figure 15). To gauge a true hunting range for each lionfish, it would be necessary to mark all possible den sites and monitor hunting behavior outside of each, preferably with GPS tagging.

19 18 Figure 13: Esme in hunting posture, stalking dash gobies in the sediment. Size: 9cm; depth,.5m Figure 14: Lionel resting upside down in den on Reef #2. Size: 12cm; depth: 3m

20 19 Figure 15: A Porcupinefish took up residence in a den previously used by Bruno and Lolita. Due to the unpredictability and movement of the lionfish, there were some sources of error which could be accounted for in future studies. The first of these is that there was no way to know with absolute certainty that the lionfish studied in each den was the same from day to day. Steps were taken to confirm the identity all fish, but without proper tagging it was impossible to know if a new fish had moved into a den site. Another source of error came from being unable to find lionfish near their dens for observation. Of all 8 lionfish, 5 were observed for the full 8 hours, but 3 came up missing on occasion and could not be found anywhere nearby. There are several possible explanations for this. The first is that the lionfish were made wary by the presence of humans nearby and sought shelter in other dens. Another is that, as was shown on Reef #2, the lionfish did not always maintain the same den and may have swam great distances from one to the other. It is also possible that some of the lionfish traveled to deeper benthic regions to hunt, as was seen to be the case on Reef #1. Finally, because lionfish have cryptic camouflage, they can effortlessly hide in a variety of coral substrates. Combined with the low visibility during crepuscular hours, this made the lionfish a difficult animal to track. A final source of error came in not being able to effectively observe all lionfish at all times. Because there were 2-3 lionfish on each reef, it was necessary to alternate the time spent watching behaviors every 5 minutes. This meant that there were some behaviors which were not

21 20 recorded. In the future, having a second or third researcher present would greatly help to minimize the loss of visibility. There are also gaps in the observation time from 8:30am-11am, 1:30-3pm, and 6:30pm-6:30am. More research is needed to effectively quantify a lionfish s true hunting range. Some strategies for implementation include choosing a larger population, tagging lionfish with GPS trackers, and marking all den sites found on the reef. This could give a true indication of how much reef a lionfish population can cover while hunting. In addition, more reefs around Guna Yala should be included in future research to confirm the results in this study. Conclusions 1. The data collected in this study indicate that lionfish around El Porvenir do maintain territorial dens which can be confirmed from day to day with roughly 50% certainty. 2. Lionfish maintain an average hunting radius of 3-6m around their den site, although they do keep more than one den and may travel large distances from one den to the other. 3. Lionfish are confirmed to be crepuscular hunters, and they are most active at sunrise and sunset where light is low enough to keep them hidden from predators and prey. 4. All of the lionfish in this study were shown to eat small teleosts. 5. Given their propensity for moving den sites, it appears that lionfish maintain a much larger hunting range than expected, and therefore have the potential to damage a reef ecosystem over a wider area than their immediate dens.

22 21 Works Cited Albins, M. A., & Hixon, M. A. (2008). Invasive Indo-Pacific lionfish Pterois volitans reduce recruitment of Atlantic coral-reef fishes. Marine Ecology Progress Series, 367, Bejarano, S., Lohr, K., Hamilton, S., & Manfrino, C. (2015). Relationships of invasive lionfish with topographic complexity, groupers, and native prey fishes in Little Cayman. Marine biology, 162(2), Gittings, S. (2017, March 3). Going Deep for Lionfish: Designs for two new traps for capturing lionfish in deep water. Retrieved March 24, 2017, from Green, S. J., Akins, J. L., & Côté, I. M. (2011). Foraging behaviour and prey consumption in the Indo-Pacific lionfish on Bahamian coral reefs. Marine Ecology Progress Series, 433, Green, S. J., Akins, J. L., Maljković, A., & Côté, I. M. (2012). Invasive lionfish drive Atlantic coral reef fish declines. PloS one, 7(3), e Humann, P., & Deloach, N. (2014). Reef Fish Identification: Florida, Caribbean, Bahamas. Jacksonville, FL: New World Publications, Inc. Lesser, M. P., & Slattery, M. (2011). Phase shift to algal dominated communities at mesophotic depths associated with lionfish (Pterois volitans) invasion on a Bahamian coral reef. Biological Invasions, 13(8), Manso, L., Ros, U., Valdés, G., del Rivero, M. A., Lanio, M. E., & Álvarez, C. (2015). Proteolytic and hemolytic activity in the venom of the lionfish Pterois volitans, an invasive species of Cuban sea coasts. Cuban Journal of Biological Sciences/Revista Cubana de Ciencias Biológicas, 4(2). Morris, J. A., & Akins, J. L. (2009). Feeding ecology of invasive lionfish (Pterois volitans) in the Bahamian archipelago. Environmental Biology of Fishes, 86(3), 389. Morris Jr, J. A., Thomas, A., Rhyne, A. L., Breen, N., Akins, L., & Nash, B. (2011). Nutritional properties of the invasive lionfish: a delicious and nutritious approach for controlling the invasion. Mumby, P. J., Harborne, A. R., & Brumbaugh, D. R. (2011). Grouper as a natural biocontrol of invasive lionfish. PloS one, 6(6), e Pimiento, C., Nifong, J. C., Hunter, M. E., Monaco, E., & Silliman, B. R. (2015). Habitat use patterns of the invasive red lionfish Pterois volitans: a comparison between mangrove and reef systems in San Salvador, Bahamas. Marine Ecology, 36(1), 28-37

23 22 Ruiz-Carus, R., Matheson, R. E., Roberts, D. E., & Whitfield, P. E. (2006). The western Pacific red lionfish, Pterois volitans (Scorpaenidae), in Florida: Evidence for reproduction and parasitism in the first exotic marine fish established in state waters. Biological conservation, 128(3), Sandel, V., Martínez-Fernández, D., Wangpraseurt, D., & Sierra, L. (2015). Ecology and management of the invasive lionfish Pterois volitans/miles complex (Perciformes: Scorpaenidae) in Southern Costa Rica. Revista de Biología Tropical, 63(1), Ruiz-Carus, R., Matheson, R. E., Roberts, D. E., & Whitfield, P. E. (2006). The western Pacific red lionfish, Pterois volitans (Scorpaenidae), in Florida: Evidence for reproduction and parasitism in the first exotic marine fish established in state waters. Biological conservation, 128(3),