Swim encounters with killer whales (Orcinus orca) off Northern Norway: interactive behaviours

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1 Journal of Ecotourism ISSN: (Print) (Online) Journal homepage: Swim encounters with killer whales (Orcinus orca) off Northern Norway: interactive behaviours directed towards human divers and snorkellers obtained from opportunistic underwater video recordings Chantal Denise Pagel, Michael Scheer & Michael Lück To cite this article: Chantal Denise Pagel, Michael Scheer & Michael Lück (2016): Swim encounters with killer whales (Orcinus orca) off Northern Norway: interactive behaviours directed towards human divers and snorkellers obtained from opportunistic underwater video recordings, Journal of Ecotourism, DOI: / To link to this article: Published online: 29 Dec Submit your article to this journal View related articles View Crossmark data Full Terms & Conditions of access and use can be found at Download by: [ ] Date: 30 December 2016, At: 00:53

2 JOURNAL OF ECOTOURISM, RESEARCH NOTE Swim encounters with killer whales (Orcinus orca) off Northern Norway: interactive behaviours directed towards human divers and snorkellers obtained from opportunistic underwater video recordings Chantal Denise Pagel a, Michael Scheer b and Michael Lück c a Johann-Friedrich-Blumenbach Institute of Zoology, Conservation Biology/Workgroup on Endangered Species, Georg-August-Universität Göttingen, Göttingen, Germany; b Independent Scholar; c School of Hospitality & Tourism, Auckland University of Technology, Auckland, New Zealand ABSTRACT Encounters of humans with wild animals should be investigated before commercial operations will be established. This study describes interactive behaviours of wild and unhabituated Norwegian killer whales (Orcinus orca) during close encounters with video-filming human divers and snorkellers. Swimmers followed a code-of-conduct to minimise disturbance. Interactive behaviours initiated by cetaceans and shown in close proximity to human swimmers can be described using an ethogram. Such a behavioural catalogue provides baseline data for managing in-water encounters. This study uses opportunistic underwater video recordings. Videos were scanned for interactive behaviours and their relative occurrence was measured. In total, eight interactive behaviours were found that are considered to be exclusively affiliative in nature. The most frequent behaviours were calling [M = 0.74] and eye contact [M = 0.67]. No aggressive behaviours were found. The present results facilitate the first description of interspecific killer whale behaviours occurring during in-water encounters with snorkellers and divers which is essential to manage interactions properly in the future. ARTICLE HISTORY Received 5 May 2016 Accepted 12 December 2016 KEYWORDS Ethogram; Orcinus orca; swim-with programmes; whale-watching; wildlife tourism Introduction As a popular segment of whale-watching tourism, commercial swim-withwhale/dolphin-programmes (SWPs) have increased in recent decades (Hoyt, 2001; Kessler & Harcourt, 2010; O Connor, Campbell, Cortez, & Knowles, 2009; Rose, Weinrich, Iniguez, & Finkle, 2005). During these, human snorkellers and divers encounter whale and dolphin individuals or groups in open-water environments (Bejder, Dawson, & Harraway, 1999; Constantine & Baker, 1997; Courbis, 2007; Curnock, Birtles, & Valentine, 2013; Delfour, 2007; Lück, CONTACT Chantal Denise Pagel chantaldenisepagel@gmail.com Arnimstrasse 79, Lübeck, Germany 2016 Informa UK Limited, trading as Taylor & Francis Group

3 2 C. D. PAGEL ET AL. 2015, 2016; Martinez, Orams, & Stockin, 2010; Samuels & Bejder, 2004). Though SWPs can represent a sustainable and environmentally friendly whale-watching activity (Allen, 2014), there are potential risks to both the animals being viewed and the tourists. SWPs were shown to increase avoidance among targeted animals (Constantine, 2001; Filby, Stockin, & Scarpaci, 2014; Kessler, Harcourt, & Heller, 2013; Martinez et al., 2010; Vermeulen, Cammameri, & Holsbeck, 2012), had an effect on activity budgets (Danil, Maldini, & Marten, 2005; Peters, Parra, Skuza, & Möller, 2013), changed aerial behaviour patterns (Courbis & Timmel, 2009), altered their acoustic communication (Scarpaci, Bigger, Corkeron, & Nugegoda, 2000), and may induce physical trauma as an indirect result of habituation (Stone & Yoshinaga, 2000). In addition to negative impacts for cetaceans, swimmers and divers are often in close and uncontrolled contact with the animals in their open-water environments, and exposed to unpredictable behaviours; dolphins have been reported to aggressively interact with swimmers and even injure and kill them (Santos, 1997; Shane, Tepley, & Costello, 1993). The possibility for injury to both animals and tourists needs to be minimised in order for wildlife tourism ventures to remain sustainable. Cetacean behaviours towards snorkellers and divers during open-water encounters have received little attention from researchers, and their structure and function mostly remain unclear. Such behaviours have been described opportunistically (see Scheer, 2010, for a review) or investigated systematically (Mangott, 2010; Scheer, Alves, Ritter, Azevedo, & Andriolo, 2014; Scheer, Hofmann, & Behr, 2004) in only some unhabituated whale and dolphin species. However, studies such as these are important to determine natural responses before commercial operations are established (International Fund for Animal Welfare [IFAW] and Tethys Research Institute and Europe Conservation, 1995; Samuels, Bejder, & Heinrich, 2000). Typical behaviour patterns that form the basic behavioural repertoire of a given species can be described and catalogued in an ethogram (Lehner, 1987). Such ethograms are required in order to pursue further behavioural analysis. While Martinez and Klinghammer (1978) compiled an ethogram describing intraspecific behaviours among captive killer whales (Orcinus orca), behaviours initiated by wild killer whales and addressed towards humans during SWPs remain unstudied. Orca watching and SWPs in Northern Norway Orca watching has become an important attraction in Northern Norway during wintertime (October to March), particularly around Tysfjord, where this activity started in the early 1990s (Damsgård, 2000; O Connor et al., 2009; Stenersen & Similä, 2004). During winter, spring-spawning herring (Clupea harengus) enter Norwegian fjords while groups of killer whales follow to prey on them (Similä, Holst, & Christensen, 1996). The population size comprises at least 600 individuals (Kuningas, Similä, & Hammond, 2007) and local abundance was shown to

4 JOURNAL OF ECOTOURISM 3 correlate with spatial fluctuations of herring (Similä et al., 1996; Stenersen & Similä, 2004). Due to a decrease in herring and subsequently killer whale abundance in recent years, the annual number of whale watchers was estimated to decrease from 5500 to 2500 (O Connor et al., 2009). SWPs with wild killer whales are exclusively conducted in Northern Norway and have shifted to an area between Andenes and Tromsø. An internet search for the 2016/2017 season revealed that about 11 commercial operators offer SWPs and mainly frequent this area and the waters of Tysfjord. They conduct single-day excursions using small inflatables and medium-sized former fishing vessels or catamarans for weekly trips carrying a maximum of 8 and 12 passengers, respectively. However, detailed information on the number of tourist arrivals, expenditures or swimmers in the area is still not available. Next to the varying and unpredictable killer whale abundance, the establishment of commercial SWPs in the area is further complicated by its remoteness, cold water temperatures (<5 C), rough sea conditions, and limited daylight (<5 h) during the SWP season. According to Samuels et al. (2000), the targeted animals are not habituated to encounters with human snorkellers and divers as only infrequent and seasonally restricted in-water interactions in varying geographic areas have occurred in the past. The present study aimed to establish an ethogram describing behaviours of unhabituated killer whales, towards human snorkellers and divers, by using opportunistic underwater video recordings. Methodology An exploratory approach was conducted to identify and catalogue behaviours of killer whales during in-water encounters with snorkellers and divers. Next to data obtained from encounters initiated and video-documented by the first author in a scientific context, additional video material from non-scientists was used for analysis. In January 2015, the village Hamn on Norway s second largest island, Senja, was used as a field base for data collection (Figure 1). Orca groups were encountered in an area between Hamn harbour, Bergsøyan, the bays Ballesvika, Teistevika and its western tip, Teistneset (Figure 2), in relatively shallow waters ( m) using an eight-metre-long sailing vessel. An own boat was used to focus on non-touristic encounters. During touristic encounters, swimmer groups are often larger (>2 persons) and swimmers are potentially unexperienced snorkellers. Furthermore, they might elicit disturbance or provoke avoidance by inappropriate behaviours such as touching attempts or too close approaches. So far, there are no existing strict guidelines regulating swim encounters in Northern Norway. The first author and the additional filmmaker both are experienced snorkellers and certified scuba divers. They have visited the study area several times. During encounters they were wearing snorkelling gear and drysuits. Undersea Soft Encounter Alliance guidelines for encounters with marine mammals were followed. To minimise

5 4 C. D. PAGEL ET AL. Figure 1. Location of study site. disturbance, both entered the water quietly, stopped their forward movement and remained passive on the water surface when the animals were in sight. During 6 days, a total of 27 hours and 35 minutes were spent at sea. When detected, focal killer whale groups were approached during feeding, travelling and resting behaviour (for definitions see Ford, 1989; Strager, 1995), and during tight (<10 m distance between individuals) or loose (<100 m) group formations. Vessel speed during approaches varied from one to six knots, depending on the behavioural state of the focal group. During relatively stationary behaviour (feeding and resting), encounters were initiated. An encounter is defined as a swim with one or more individual/s in visual range underwater (<20 m) for 15 seconds or more (Scheer, 2010). Swim encounters were terminated when the animals departed from the area and underwater visual contact terminated for more than five minutes. Encounters were documented using a Sony Action-Camcorder HDR-AS100V in an underwater housing. Two inwater encounters were initiated during a single day. During these, two videos with a total duration of 22 minutes 56 seconds were collected.

6 JOURNAL OF ECOTOURISM 5 Figure 2. Area of research. Weather and sea conditions such as snowfall, strong winds and Beaufort states >5 as well as limited daylight (<6 hours/day) prevented boat trips or complicated visual search for the animals. As a result, scientific data collection on site was low and additional video material from non-scientists was used. Footage was obtained from three professional filmmakers using snorkelling and diving gear. They filmed killer whales underwater in the same and adjacent areas over several years ( ). To avoid disturbance, all filmmakers applied the same encounter methodology as described above. Their total footage length was 124 minutes 36 seconds. Though filmmakers used different recording equipment, all videos enabled equal visual and acoustical analysis. However, as these persons did not conduct encounters in a scientific context, the sampling protocol as described above remains unclear, and may have varied for different persons. Video durations ranged from 8 seconds to 19 minutes 14 seconds (mean ± SD: 2.54 ± 3.28 min, n = 56). All footage was initially inspected for interactive behaviours using the ad libitum method (Altmann, 1974; Martin & Bateson, 1993). Interactive behaviours were defined as behaviours initiated by an individual or a group of killer whales, and directed towards a swimmer within a human body length (<2 m) to 20 m range. Based on Scheer (2010), interactive behaviours were categorised as (a) affiliative/neutral when there were no signs of threat or aggression, (b) as aggression/threat when they put swimmers at health risk and/or the same behaviour was observed by other researchers during agonistic intraspecific interactions among killer whales or other

7 6 C. D. PAGEL ET AL. toothed whale species (Dudzinski, 1996; Herzing, 1996; Martinez & Klinghammer, 1978; Shane, 1990), or (c) as sexual when sexual behaviours were directed towards swimmers, putting them at health risk. After establishing an á priori ethogram containing all behaviours detected during the initial inspection, all videos were analysed a second time. The occurrence of each type of interactive behaviour per video was measured on a one/ zero basis, which Martin and Bateson (1993) described as a reliable method for recording intermittent behaviour with the recording sessions divided into short sample intervals. The rate by one/zero sampling is scored as the proportion of all sample intervals during which the behavioural pattern has occurred (Martin & Bateson, 1993). Results The ethogram describes eight different behaviours (Table 1) which were all affiliative in nature. No aggressive/threatening or sexual behaviours were observed. The variability of different behaviours occurring during a single video was 0 8 (mean ± SD: 3.40 ± 0.06). One/zero values of behaviours ranged from 0.07 to 0.74 (Table 2). Most common behaviours were calling, occurring during 43 clips (one/zero value = 0.74), and eye contact, occurring during 39 videos (0.67). Echolocation (0.62), close approach (0.48) and head orientation (0.38) were also common behaviours whereas belly up approach (0.21) was less common. Encircling and bubble release were only observed during six (0.10) and four (0.07) videos, respectively. Table 1. Overview of interactive behaviours of Norwegian killer whales addressed towards human snorkellers and divers. Behaviour Code Description Belly up approach BA An animal frontally approaches a swimmer from a distant position (5 20 m) with a horizontal and dorsal orientation to the water surface. While reaching a close proximity to the swimmer (less than two swimmer body lengths), the animal turns belly up and emits clicks towards the person. The animal glides along the whole body axis of the swimmer (distance to the swimmer is one body length) who is lying motionless at the water surface. While in the ventral position towards the swimmer, the animal has a stereoscopic eye contact. Bubble release BR Animal releases bubbles from its blowhole while in close proximity to the swimmer/s. Calling C Animal emits whistles/calls while in close proximity (<10 m) to the swimmer. Close approach CA Animal closely approaches human swimmer/s (<5 m) with a horizontal and dorsal orientation to the water surface. The animal turns to the left or right while entering a 2 5 m proximity to the swimmer. Echolocation ELO Animal emits clicks while in close proximity (<10 m) to the swimmer/s. Encircling ENC An animal approaches a swimmer from a distance (5 20 m) and then swims around in circles once or several times. The radius is small (<two swimmer body lengths). The animal is positioned at the water surface during its circle track. Eye contact EC Animal has eye contact with swimmer while in close proximity (<5 m). Head orientation HO Animal turns its head towards swimmer when passing by.

8 JOURNAL OF ECOTOURISM 7 Table 2. Total and mean one/zero occurrence of interactive behaviours during 58 videos. Behaviour n (total) Mean one/zero C EC ELO CA HO BA ENC BR Discussion Norwegian killer whales showed eight interactive behaviours that were all affiliative in nature. Some of these were also described for other unhabituated cetacean species during in-water encounters with human swimmers, for example, roughtoothed dolphins (Steno bredanensis; Kuczaj & Yeater, 2007; Ritter, 2002), dense-beaked whales (Mesoplodon densirostris; Ritter & Brederlau, 1999), and short-finned pilot whales (Globicephala macrorhynchus, (Scheer et al., 2004, 2014; Shane et al., 1993). Neither agonistic behaviours, like the reported headshake in short-finned pilot whales (Scheer et al., 2004), nor threat displays (e.g. an open mouth; see Shane et al., 1993) were observed during this study. Both behaviours were found among captive killer whales during intraspecific interactions (Martinez & Klinghammer, 1978). However, the absence of aggressive/threatening and sexual behaviours during this study has to be interpreted with caution. As data quantity is relatively small for this study, further observations might reveal additional behaviours. Furthermore, the applied swim approach procedures might prevent agonistic or sexual behaviours. Swimmers (including filmmakers) avoided any physical contact with the animals, since touching was interpreted as a catalyst for aggressive interactions (e.g. Goffman, Lavalli, Kerem, & Spanier, 1999; Mann & Smuts, 1999; Scheer et al., 2004, 2014; Shane et al., 1993). The absence of touching during this study might explain the absence of aggressive behaviours. The use of underwater video footage from non-scientists is promising and can deliver additional insights for the study of SWPs. Especially when the study area is remote and data collection is challenging due to restrictive weather conditions and daylight hours. Furthermore, SWPs have been studied using boat- or landbased observation platforms (Constantine, 2001; Martinez et al., 2010; Peters et al., 2013; Vermeulen et al., 2012). However, behavioural details during inwater encounters can only be observed from the underwater perspective. Videos obtained from non-scientists during this study contributed to cataloguing interactive behaviours during SWPs, but the absence of a consistent sampling protocol and the lack of systematic data (group size and composition, surface behaviour before SWP, encounter lengths) limit their scientific use. It has

9 8 C. D. PAGEL ET AL. often been the case that filmmakers switch off the camera during a single encounter, which prevents measuring the encounter length, and it remains unclear when footage originates from the same encounter, or whether the recording contains different focal groups. Conclusions For the first time, this study provides insights into in-water encounters of human swimmers with unhabituated killer whales. In the literature, swimming with cetaceans has been discussed controversially. While free-ranging animals have the choice to maintain or terminate encounters, they might also become habituated to human contact and negatively impacted during encounters or exposed to indirect effects. The risk of injury to both humans and animals has been pointed out as a key problem for swim-with activities (Allen, 2014). The economic attractiveness for operators depends on the stability of killer whale abundance in the area which was shown to fluctuate in recent years. Thus, swimmer numbers off Northern Norway have been low so far and it remains to be seen how killer whales will behave when commercial operations and annual swimmer numbers might increase. Research found that some photo-identified individuals were re-sighted in the area during successive seasons and at least some of the animals have been identified as annual visitors (Similä et al., 1996; Similä 2015, personal communication). Consequently, it is possible that distinctive groups or individuals are more frequented by swimmers than animals visiting the area once or irregularly. During this study, the animals were not photo-identified, and it is recommended that future studies include individual identification of animals involved in swim activities with humans in order to enable the monitoring of potential habituation effects. Furthermore, age/sex-related analysis of interactive behaviours will enable additional insights into probable group dynamics during swim encounters. It is strongly recommended to intensify studies on swim encounters and to monitor them to deliver baseline data for management activities. Acknowledgements We would like to thank Marco von der Schulenburg, Dr Florian Graner and Steffen Schmitt for kindly providing access and footage, as well as Dr Matthias Waltert for providing supervision. Thanks to the Resort Hamn i Senja for hosting during field work and to OASIS Diving, Göttingen. Thank you to the anonymous readers for their constructive comments, which greatly improved the paper. Disclosure statement No potential conflict of interest was reported by the authors.

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