Social Dominance and Male Breeding Success in Captive White-Tailed Deer

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1 Peer Reviewed Social Dominance and Male Breeding Success in Captive White-Tailed Deer RANDY W. DEYOUNG, 1 Department of Wildlife and Fisheries, Mississippi State University, Mississippi State, MS 39762, USA STEPHEN DEMARAIS, Department of Wildlife and Fisheries, Mississippi State University, Mississippi State, MS 39762, USA RODNEY L. HONEYCUTT, Department of Wildlife and Fisheries Sciences, Texas A&M University, College Station, TX 77843, USA KENNETH L. GEE, Samuel Roberts Noble Foundation, Allen, OK 78425, USA ROBERT A. GONZALES, Samuel Roberts Noble Foundation, Ardmore, OK 73402, USA Abstract Management strategies that incorporate the social behavior of wildlife may be more efficient in achieving population objectives. Our current knowledge of white-tailed deer (Odocoileus virginianus) social behaviors may not be adequate for application to management. Using captive white-tailed deer, we investigated the long-held assumption that relatively few dominant males sire most offspring and, thus, prevent subordinates from breeding. Although this assumption influences population predictions and management strategies, empirical studies of the relationship between dominance and male breeding success in deer are lacking. We determined male dominance rank and genetic paternity through 6 breeding trials. Although dominant males sired most offspring, subordinates sired offspring in 5 of 6 trials and multiple paternity (siring of offspring by 2 males) occurred in ;24% of compound litters. Further, male dominance ranks were not necessarily predictable or stable during the breeding season. This study indicates that the relationship between social dominance and male breeding success may be more complex than previously thought. Our findings also are consistent with recent studies of parentage in wild deer, providing additional evidence that social dominance does not necessarily equate to breeding success. Conceptual models of deer breeding behaviors should account for considerable individual heterogeneity among males in their ability to sire offspring. (WILDLIFE SOCIETY BULLETIN 34(1): ; 2006) Key words behavior, breeding success, Odocoileus virginianus, parentage, paternity, social behavior, white-tailed deer. Reliable knowledge of animal social behaviors may be used to increase the effectiveness of management strategies (e.g., Porter et al. 1991) and offer more realistic predictions of population responses to management actions (Côté 2003). Many authors have advocated an increased consideration of social behaviors in the management of wildlife (see Festa-Bianchet and Apollonio 2003), including white-tailed deer (Odocoileus virginianus; Porter et. al. 1991, Miller 1997, Miller and Ozoga 1997). However, the existing knowledge base on white-tailed deer social behaviors has been criticized as simplistic (Miller and Ozoga 1997), based on anecdotal evidence or a small number of visual observations. Therefore, the current state of knowledge regarding social behaviors may not be adequate to gauge effects of current management practices on or support the development of new management strategies for white-tailed deer. For instance, the breeding structure of white-tailed deer has been described as dominance-based (Hirth 1977, McCullough 1979, Marchinton and Hirth 1984). Among males, dominance and social rank often are associated with physical traits, such as age and body mass, with the top ranks in dominance hierarchies held by mature, large-bodied individuals (Townsend and Bailey 1981, Miller et al. 1987). Because physical maturity and maximum body mass in males are attained after 4 years of age (Sauer 1984, Strickland and Demarais 2000), this is presumably when males hold their maximum dominance ranks. A relatively few dominant males are assumed to sire most offspring in age-structured populations, while the reproductive performance of subdominants is thought to be 1 randall.deyoung@tamuk.edu 2 Present address: Caesar Kleberg Wildlife Research Institute, Texas A&M University-Kingsville, Kingsville, TX 78363, USA suppressed through behavioral interactions (Hirth 1977, McCullough 1979, Marchinton and Hirth 1984, Miller and Ozoga 1997). The assumption of a dominance-based breeding hierarchy, where most offspring are sired by a few dominant males, is a central tenet of deer ecology and management, affecting both population predictions and management strategies. For instance, some degree of inbreeding is hypothesized to occur because a male may remain dominant in an area for several years, breeding within the same matriline (Nelson and Mech 1987). Estimates of breeding gender ratios disregard young males (,3 years of age) as unlikely to breed (Cronin et al. 1991). Changes in male age structure due to intense harvest are predicted to result in reduced in population fitness over extended time periods because dominance-based breeding becomes a scramble competition, allowing less-fit males to breed (Ozoga and Verme 1985, Miller and Ozoga 1997). Young males are assumed to invest few resources in reproductive efforts in the presence of physically mature males (Miller and Ozoga 1997). Finally, the recent increase in the intensive management of white-tailed deer (e.g., Demarais et al. 2002) has led some to recommend protecting mature large-antlered males as breeder bucks in an effort to increase population antler size, assuming these individuals will sire many offspring (see Rollins 1998). We contend that the importance of social dominance in the breeding success of white-tailed deer is questionable because this tenet is largely based on circumstantial evidence. Studies using genetic paternity assignment in populations of large mammals increasingly have revealed patterns of breeding success that differ from those based on visual observations (Pemberton et al. 1992, Amos et al. 1995, Hogg and Forbes 1997, Coltman et al. 1999, DeYoung et al. White-Tailed Deer Breeding Success 131

2 Pemberton et al. 1999). The disparity between visual and genetic measures of paternity occurs primarily because not all individuals or copulations can be observed and because copulation does not necessarily result in conception. Surprisingly, dominance does not always equate to breeding success because males of all ages and dominance ranks may successfully employ alternative breeding tactics that do not rely on dominance (e.g., Hogg and Forbes 1997, Pemberton et al. 1999, Worthington Wilmer et al. 1999, Gemmel et al. 2001). Furthermore, recent studies of genetic paternity in white-tailed deer do not support the previously described dominance-based breeding hierarchy. First, multiple paternity in single litters of white-tailed deer was found to occur at a high rate (ca % of compound litters) in both captive and wild deer (DeYoung et al. 2002, Sorin 2004, R. DeYoung, unpublished data). Second, patterns of parentage and relatedness in cohorts of free-ranging white-tailed deer indicate that breeding success is distributed among many males in all age classes; breeding is clearly not monopolized by one or a few males (DeYoung 2004, Sorin 2004). One explanation for the apparently reduced importance of dominance in male breeding success is that opportunities to exercise dominance may be limited by behavioral or habitat characteristics (Say et al. 2001, DeYoung 2004, Sorin 2004). However, several alternative explanations remain plausible. First, dominance may appear less important to male breeding success due to the successful employment of alternative breeding tactics. Second, physical attributes assumed to convey dominance (e.g., age, body mass) may not be correctly assessed in the field, resulting in misleading conclusions. Third, dominance may not be stable throughout the entire breeding season, allowing a greater number of males access to breeding opportunities. To develop a useful conceptual model of breeding behavior in white-tailed deer, we must determine if behaviors are predictable. The logistical difficulties of conducting intensive behavioral studies in a free-ranging population of white-tailed deer are formidable. Furthermore, visual observation alone is an inadequate and potentially highly misleading method for paternity assignment (Amos et al. 1995, Hogg and Forbes 1997, Pemberton et al. 1999, Worthington Wilmer et al. 1999, Gemmel et al. 2001). To mitigate for these circumstances, we initiated a study in a controlled environment, using a captive population of white-tailed deer. We determined male dominance ranks from behavioral observations during the breeding period, then assigned genetic paternity of the resulting offspring using a panel of DNA microsatellite loci. Our overall goal was to investigate the role of social dominance in male breeding success. Specific objectives were 1) to determine if male dominance was associated with breeding success, 2) to determine if subordinate males were able to secure matings, and 3) to determine if male dominance ranks were predictable based on easily quantified physical characteristics such as age and body mass. Methods Deer Handling and Sample Collection We conducted the study in the Wildlife and Fisheries Research and Education Facility at Mississippi State University. We held the deer used to conduct the study in 3 pens ranging in size from ha. We allowed different groupings of males and females to breed each year and housed surplus males separately. We chose individual deer in the study to avoid close inbreeding (e.g., father daughter matings). Deer density did not exceed 20/ha. Research methods were approved by the Mississippi State University Institutional Animal Care and Use Committee, Protocol We randomly allocated groups of different-aged males (3 males per group) to 2 breeding pens each year during autumn (corresponding to offspring birth years ), resulting in 6 breeding trials during this 3-year period. Male groups consisted of 2 age structures: a compressed age structure containing 2 yearling males and one 2.5-year male, or a diverse age structure containing males aged 1.5, 3.5, and 5.5 years. Each age structure was represented by 3 trials. Seven to 12 adult (1.5 years of age) females were allocated randomly to each breeding pen depending on the number of deer available each year. We assigned deer to pens during early October, coinciding with antler hardening. Due to the potential for injury to staff and other deer from antler punctures, we sedated all males and removed antlers 6 cm above the burr. A description of sedation procedures may be found in DeYoung et al. (2002). During sedation, we obtained body mass for each male and inspected for signs of injury or illness that could affect their interactions with other males. We manually restrained adult females and fawns or herded these deer through gated lanes to facilitate separation and transfer among pens. We obtained 3 5 ml of blood by venipuncture from all adult deer and stored at 48C in vacuum tubes containing EDTA (Vacutainer, Becton-Dickson and Company, Franklin Lakes, New Jersey). We manually restrained offspring within 1 3 days postpartum and obtained circular ear plugs (0.5 cm in diameter), which we preserved in 70% ethanol. During autumn 2000, we collected semen from 13 of the 18 males used in the study (5 males used in were deceased) for a breeding soundness evaluation. We obtained ejaculates under sedation using an electroejaculator (Pulsator IV, Lane Manufacturing Inc., Denver, Colorado) and a 3-pronged ram probe according to the methods of Jacobson et al. (1989). Ejaculation occurred between mv. A licensed veterinarian performed scrotal palpation and evaluated semen motility and morphology to ensure that all males were physiologically capable of siring offspring. Behavioral Observations We used behavioral observations to index male dominance ranks. We first estimated offspring conception dates from birth dates of fawns born in the facility during previous years (S. Demarais, Mississippi State University, unpublished data) assuming a 200- day gestation (mean of reported white-tailed deer gestation periods; Haugen and Davenport 1950, Haugen 1959, Adams 1960, Verme 1965). Based on this information, we conducted observations from about 15 November 15 January with the exception of a 2-week period during university winter holidays in late December (ca. 23 December 3 January). Observers were present during ;80% of conception dates. We performed observations with the aid of binoculars from permanent stands or temporary blinds in trees in or surrounding each pen. Five observers assisted during the study. Observation periods lasted a minimum of one hour and were conducted at varied times during 132 Wildlife Society Bulletin 34(1)

3 daylight hours. We attempted to observe each pen at least twice weekly. We continuously viewed all males within a single pen during an observation period. We inferred male social hierarchies from direct aggressive submissive encounters between males or from indirect behaviors (e.g., avoidance or isolation) using behavioral cues described by Hirth (1977), including pursuit and courtship of females, rub-urination, and scraping behavior, while paying close attention to each deer s posture (including position of the ears), and remaining alert for any direct stares, erector pili, etc. DNA Amplification and Parentage Assignment We used genetic paternity to determine the breeding success of males in relation to dominance rank. We isolated DNA from whole blood or ear plugs as described previously (DeYoung et al. 2002, 2003). We amplified 17 DNA microsatellite loci and constructed multilocus genotypes for all individuals (Anderson et al. 2002, DeYoung et al. 2003). We assigned parentage for all fawns using a likelihood ratio method in the computer program CERVUS 2.0 (Marshall et al. 1998). The software also provides estimates of mean allelic diversity (A), expected multilocus heterozygosity (H), mean polymorphism information content (PIC), and exclusion probabilities. Results The study population consisted of 43 adult deer that produced 100 fawns. The microsatellite markers were highly variable (A ¼ 9.9; H ¼ 0.70) and informative (PIC ¼ 0.66; exclusion probability.0.99) in this captive group. Sires were assigned for offspring born during the study in all but 2 cases, where amplifiable quantities of DNA could not be extracted from fawn samples. A single male (1.5 years of age) died during the breeding season due to an unidentified infection (pen 1999a; Table 1) and was not replaced, leaving only 2 males (aged 3.5 and 5.5 years) for this trial. The breeding soundness evaluation indicated that all males examined were physiologically capable of siring offspring (DeYoung et al. 2004). Although 5 males in were deceased when the evaluation was performed, there is no reason to believe that they were sterile; 4 of the 5 sired offspring. Male dominance rank remained constant throughout the observation period in 4 of the 6 pens (Table 1). In the other 2 trials, male dominance shifted during the study. The dominance status of the male affected the number of offspring sired, with the dominant males siring % of fawns in the 4 pens where dominance rank remained constant (Table 1). In the 2 pens where dominance shifts occurred, the precise time of dominance shift could not be pinpointed. Rather, there appeared to be a period of transition (at least 2 3 weeks) during which the formerly subordinate male supplanted the dominant male. In general, the parentage assignment results reflected these shifts in dominance (Table 2). In the 1999a pen, the 5.5-year male (initially dominant) sired the first litter produced and shared paternity of the third and sixth litters. In the 2001b pen, the 6.5-year male (initially dominant) sired the first and second litters and shared paternity of the fourth and sixth litters. There was a clear association between dominance and age only among 1.5- and 2.5-year males, where 2.5-year males were dominant in all 3 pens. In pens containing males aged 3.5 and 5.5 years, the 3.5-year male was dominant throughout the study in 1 case and 3.5-year males achieved dominance during the breeding period in the other 2 trials. Male body mass was generally associated with age. With 1 exception (3.5-year male, pen 1999b; Table 1), the oldest male in each pen had the greatest body mass, though differences in mass between males aged 3.5 and 5.5 years were not great ( kg) and the masses of same-aged males were variable (Table 1). For males 2.5 years of age, 2.5-year males always outweighed 1.5-year males. It is interesting to note that the only 1.5-year male to sire.1 fawn was Table 1. Pen setup, male dominance status, and number of fawns sired by male white-tailed deer in experimental breeding pens at the Mississippi State University Captive Animal Facility during Pens are identified by offspring birth year. Pen number No. of females 1.5 years Male age (years) Body mass (kg) Dominance status No. of fawns sired 1999a a 10 b a b Subordinate Dominant Subordinate a Subordinate 1 c Subordinate Dominant b Subordinate Subordinate 7 d Dominant a Subordinate Subordinate Dominant b Subordinate 1 e f f 5 a The 5.5-year male was initially dominant, became subordinate to the 3.5-year midway through the breeding season. b These 2 males shared paternity of 2 litters. c Shared paternity of 1 litter with 2.5-year male. d Shared paternity of 3 litters with 2.5-year male, sired 2 litters independently. e Shared paternity of 1 litter with 3.5-year male. f The 6.5-year male was initially dominant, became subordinate to the 3.5-year male midway through the breeding season. DeYoung et al. White-Tailed Deer Breeding Success 133

4 Table 2. Birth chronology of offspring, sire age, and dominance status in 2 pens of captive white-tailed deer at the Mississippi State University Captive Animal Facility during 1999 and Pen 1999a Pen 2001b Litter a Date of conception Sire age Litter a Date of conception Sire age i (2) 2 December 5.5 i (2) 1 December 6.5 ii (1) 11 December 3.5 ii (2) 11 December 6.5 iii (3) 16 December 3.5, 5.5 iii (1) 16 December 3.5 iv (2) 16 December 3.5 iv (2) 20 December 3.5, 6.5 v (2) 20 December 3.5 b v (2) 28 December 3.5 vi (2) 23 December 3.5, 5.5 vi (1) 22 February 6.5 vii (2) 9 January 3.5 viii (1) 24 January 3.5 a Roman numerals indicate birth order (based on estimated conception dates), numbers in parentheses indicate number of fawns. b Shared paternity with a third male that gained temporary access when an interior fence was damaged. the heaviest male in this age class during the study, outweighing the other year males by an average of 16.2 kg (SD ¼ 6.2). The pens were part of a study describing the occurrence of multiple paternity in white-tailed deer (DeYoung et al. 2002), which found 7 of 27 compound litters (twins or triplets) to be sired by 2 males. Multiple paternity occurred at a similar rate during The 4 pens in 2000 and 2001 produced 24 compound litters, 5 of which were sired by 2 males. Combined, multiple paternity occurred in 12 of 51 compound litters (24%). Discussion Our study, the first to examine the relationship between social dominance and genetic paternity in white-tailed deer, revealed some important insights relevant to the role of dominance in male breeding success. In captivity, dominance was associated with breeding success, but dominants could not monopolize breeding as evidenced by repeated occurrences of multiple paternity and siring of offspring by subordinates in 5 of 6 trials. More problematic from a manager s perspective, male dominance ranks were not necessarily predictable or stable during the breeding season, a situation also observed by Walock (1997). Townsend and Bailey (1981) found that male social rank was correlated with body mass and that age was not necessarily a factor in social position after 2.5 years of age. Similarly, Miller et al. (1987) concluded that social rank was influenced by body mass and age as well as other factors. In this study, the heaviest male was initially dominant in all trials. However, differences in body mass among males 3.5 years of age were relatively minor, which may partially explain the vagility of dominance ranks among these age groups during the study. Regardless, we observed considerable heterogeneity in the stability of dominance ranks and the ability of males to secure matings. Although there are many advantages to studying deer behaviors in a captive setting, caution must be exercised in extending the results to free-ranging deer. A prime example is the findings of Alexy et al. (2001), who demonstrated that signpost (scraping) behavior in free-ranging white-tailed deer did not reflect the behaviors described in captive deer. In addition to the confined conditions of this study, another difference between our captive group and wild deer is that antlers were removed from males due to safety concerns, possibly affecting interactions among males. However, antler size alone does not define dominance in whitetailed deer; studies of captive deer indicate that age and body mass are important determinants of dominance (Townsend and Bailey 1981, Miller et al. 1987). If there was a clear, consistent relationship between dominance and breeding success, one would expect dominants to be more effective at suppressing the performance of subordinates under confined conditions, where dominants can keep all females in view and quickly interfere with any breeding attempts by subdominants. In fact, this did not happen, suggesting that the ability of dominant males to suppress the breeding of subdominants in free-ranging populations is limited to interactions over individual females. In recent studies of wild white-tailed deer, genetic parentage data clearly indicates that physically immature males (,3.5 years of age) are breeding in several age-structured populations, with no evidence of any individual male able to monopolize breeding (DeYoung 2004, Sorin 2004). These findings, as well as others (Hogg and Forbes 1997, Ambs et al. 1999, Coltman et al. 1999, Gemmel et al. 2001), indicate that dominance does not necessarily equate to breeding success in species of large mammals. Why is dominance not as important to male breeding success in whitetailed deer as previously thought? The use of alternative mating tactics can not be ruled out since subordinates did breed successfully in captivity and clearly do breed in wild populations. Male white-tailed deer engage in a behavior termed tending, where a male temporarily guards an estrous female from other males (Hirth 1977), a behavior thought to be a mechanism for ensuring paternity (Emlen and Oring 1977, Clutton-Brock 1989). Although some have proposed that multiple paternity in whitetailed deer occurs when a tending male is displaced by another male while the female remains receptive (DeYoung et al. 2002, Sorin 2004), an alternative explanation is that multiple paternity may occur through the use of alternative mating tactics by subdominant males (e.g., Hogg and Forbes 1997, Preston et al. 2003). Similarly, changes in dominance ranks among individuals during the breeding season can not be ruled out as a partial explanation for the observed patterns of breeding in wild deer. Dominance ranks were not predictable or stable in captivity and the same may occur in wild populations. However, direct evidence for alternative mating tactics or dominance shifts in wild white-tailed deer is lacking and seemingly inadequate to explain the patterns of male mating success observed in wild populations. The departure from the accepted dominance-based breeding hierarchy may best be explained by behavioral and ecological factors. Unlike in captive 134 Wildlife Society Bulletin 34(1)

5 deer, the dense cover and patchy distribution of resources in white-tailed deer habitats inhibits the formation and maintenance of large groups (Demarais et al. 2000), ruling out territoriality or harem defense as viable male mating strategies (Clutton-Brock 1989). Male mating tactics consist of roaming widely in search of individual estrous females, spending up to 24 hours tending each receptive female (Hirth 1977); most conceptions occur in a relatively short period of time (2 4 weeks in temperate populations; Marchinton and Hirth 1984). The overall spatial dispersion of females within populations combined with temporal synchrony of estrous would limit the number of estrous females an individual male can locate and breed, allowing more males access to mating opportunities and restricting the success of individual males (e.g., Say et al. 2001). Therefore, competition among males is not necessarily population-wide, but probably limited to a subset of males that has located the same estrous female. During times when many females are in concurrent estrous, subdominants would not necessarily be forced to challenge dominants for breeding rights, allowing males to secure breeding opportunities regardless of dominance status. Although it is clear that a greater number of males are breeding than expected in wild deer, the physical attributes that influence breeding success are not known. Further, demographic and ecological factors (e.g., age structure, density, gender ratio, distribution of resources, synchrony of estrous; Langbein and Thirgood 1989, Clutton-Brock et al. 1997, Komers et al. 1997, Ambs et al. 1999, Coltman et al. 1999, Hoelzel et al. 1999, Pemberton et al. 1999) that affect the distribution of male breeding success in other cervids may affect white-tailed deer similarly. For instance, we have noted differences in the distribution of male breeding success among captive and field studies, suggesting that factors which influence deer movements and distribution affect breeding success. Some individual captive males can mate with a large number of females, siring a high proportion (64 100%) of the fawns produced in a pen, while the most successful wild males mated with only 6 7 females in a single year, 13% of offspring for which paternity could be determined (DeYoung 2004, Sorin 2004). Although the number of females bred per year are underestimates in wild deer because not all offspring were sampled, we have no reason to believe that the paternity assignments in these studies were biased toward certain classes of males. In contrast, Ott et al. (2003) reported that single male white-tailed deer were able to sire 26 and 64% of offspring in each of ha enclosures populated by wild deer, approaching the level of breeding success observed in captive deer. The difference in mating skew among these situations suggests some effect of enclosure size on the mating success of males, possibly through restricting the movements of individual deer, thus reducing search time for mates and creating a situation where dominance conferred a greater advantage in breeding success. Management implications This and other recent studies (DeYoung et al. 2002, DeYoung 2004, Sorin 2004) question the validity of some long-held views regarding the breeding behavior of white-tailed deer. Our results indicate that dominance does not necessarily equate to male breeding success in white-tailed deer. We consider it likely that behavioral and ecological factors explain observed patterns of male breeding in wild deer. Dominance is important to male breeding success, but there are fewer opportunities to exercise dominance than previously expected. From a manager s perspective, assessing the breeding potential of individual males is tenuous because: 1) breeding is not exclusively determined by social dominance, 2) dominance ranks may not be predictable or stable, and 3) factors that determine male mating success in wild deer are not clearly understood. To date, the only promising white-tailed deer management strategy that considers social behaviors is based on conceptual models developed by Porter et al. (1991), intended for use in the localized management of female white-tailed deer. One reason that the Porter et al. (1991) hypothesis remains plausible is that the approach is based on a solid foundation of knowledge, namely a 25-year study of female group fidelity and movement patterns of free-ranging deer, and compliments similar research done in other regions (e.g., Nelson and Mech 1987). However, deer exhibit substantial behavioral plasticity across their range and even this thorough treatment may not be representative of deer behaviors in all populations, as evidenced by the high rates of female dispersal in agricultural landscapes (Nixon et al. 1991). Further research into the social behavior of white-tailed deer is clearly necessary if social behaviors are to be used in management. For now, management strategies that make assumptions about male breeding behaviors should account for a substantial amount of individual heterogeneity. Acknowledgments We thank J. R. Dawkins, S. McKinney, M. Harrison, B. Taylor, C. Carpenter, and numerous student volunteers for assistance with captive deer. T. J. Engelken performed breeding soundness evaluations. A. R. Harris and J. D. Anderson provided valuable assistance with microsatellite genotyping. Funding and support was provided by the Rob and Bessie Welder Wildlife Foundation, the Samuel Roberts Noble Foundation, and the Mississippi Department of Wildlife, Fisheries, and Parks (Federal Aid in Wildlife Restoration Project W-48 47, Study 52). This manuscript is contribution 641 of the Rob and Bessie Welder Wildlife Foundation and WF216 of the Forest and Wildlife Research Center at Mississippi State University. Literature cited Adams, W. H., Jr Population ecology of white-tailed deer in northeastern Alabama. Ecology 41: Alexy, K. J., J. W. Gassett, D. A. Osborn, and K. V. Miller Remote monitoring of scraping behaviors of a wild population of white-tailed deer. Wildlife Society Bulletin 29: Ambs, S. M., D. J. Boness, W. D. Bowen, E. A. Perry, and R. C. Fleischer Proximate factors associated with high levels of extraconsort fertilization in polygynous grey seals. Animal Behaviour 58: Amos, B., S. Twiss, P. Pomeroy, and S. Anderson Evidence for mate fidelity in the gray seal. 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