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Effects of Mating Season Based on Canis Lupus Howling Behavior
Perez, Karen
Tran Phan, Tiffany
Castellano, Jerred
Hadjih, Melissa
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Denver, CO
Metropolitan State University of Denver
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Conference Papers ( sobekcm )


Collected for Auraria Institutional Repository by the Self-Submittal tool. Submitted by Matthew Mariner.
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Mentor: Christopher Cooley
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Major: Biology

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Effects of mating season based on Canis Lupus howling behavior Jerred Castellano, Melissa Hadjih, Tiffany Tran Phan, Karen Pérez We thank Altamirano, Flores, Nguyen, and Perez (2018) for the audio recording that was reanalyzed. C . Cooley for mentoring. R . Hancock for allowing us to use his lab equipment. To Mission: Wolf for being a safe haven for the wolves. And u ltimately , we thank the wolves and their howling! Acknowledgements Introduction In the fall of 2018, a two night howling sound recording was gathered at the Mission: Wolf sanctuary in Westcliffe, CO. from Friday, September 28th to Sunday, September 30th. This data would determine the inverse correlation effects that feeding or non feeding would have on C. lupus howling patterns. The following procedure was done. On the evenings of Friday, September 28th and Saturday, September 29th, an iPhone 8 Plus was utilized as the recording device. A specialized Olympus ME 51S Stereo Microphone was hooked up, by an external microphone adapter, to the recording device for data collection. The Olympus microphone was chosen based on its high quality sound feature that had the ability to minimize the sound of the wind. The device was installed northwest and recorded from 20:30 to 07:15. A total of 11 hours and 15 minutes of audio recordings from the 25 diverse C. lupus and wolf dogs was obtained from both nights. Reflecting that of the previous study, this exact procedure would have been repeated for the 2020 spring mating season data collection. In April 2020, the fall non mating season data gathered from Altamirano et al. (2018) was reanalyzed under the newly proposed hypothesis. The model that Altamirano et al. (2018) conducted for cataloging the recordings was performed. The file was divided into the four group members. For each howl identified, three components had to be accounted for: (1) the start and stop timestamps, (2) the difference between the start and stop timestamps in seconds and (3) whether it was a solo or chorus howl. Note that a solo howl was classified as an individual howl which ends with no other howls joining. A chorus howl was classified as a group howl with 2 or more joining howls. The difference between two times (start and end) of each howl was calculated through Excel. This data would determine if the seasonal cycle had a significant factor or a direct correlation to the increase of howling patterns in C. lupus . Materials and Methods In Figure 1 ., the chart shows two nights of data and the total amount of vocalized howls in order to determine the variations between solo and chorus howling calls from C. lupus. The first night during a non fed period versus the second night during a fed period. Within the set of data for night one, there were 23 solo vocalizations and 44 chorus vocalizations which equated to a total of 67 active vocals. On the second night, there was a count of 33 solo vocalizations and 33 chorus vocalizations which equated to a total of 66 active vocals. The span of every solo and chorus howl had been tested to compare the effect of feedings on both nights. On the first night when C. lupus was not fed the vocalizations totaled to 1,984 seconds (Two sample t test, d.f = 132, p = 0.49) in comparison to the second night, which had a lengthier duration time due to C. lupus being fed, that totaled to 2,158 seconds (Two sample t test, d.f = 136, p = 0.49). Equating both the solo and chorus howls, a total of 156 seconds of solo howling calls were identified on the first night and 275 seconds of solo vocalizations were identified on the second night. As for chorus callings, the sum of 1,828 seconds of howls was recorded on the first night and 1,883 seconds of howl vocalizations were recorded on the second night. The data was collected roughly throughout the dusk and dawn parts of the day. Due to C. lupus being nocturnal (active at night) the time frame from dusk to dawn played a role in the data that had been collected. Note: dusk referring to the twilight period of the night and dawn referring to the early morning period of the day. Overall, the recording lasted from approximately 20 :30 to 7:15. The contrast, as shown in Figure 2 ., between the count of vocal howlings during the dusk and dawn periods is as follows . The data at dusk was retrieved from 20:30 until 1:45 while the dawn data was collected from 1:45 until 7:15. On the first night during the dusk period, the sum of three howls was identified and a sum of 64 howls during the dawn time was discerned. On the second night, no howling vocals during the dusk period were observed, although 66 vocalizations throughout the dawn period were. The period of howling at dusk marked 4.5 % in comparison to the excessive 95.5 % of howling occurring during the dawn period. Results A Canis lupus ) prime form of vocalized communication during mating season is howling. The howls made by C. lupus are long range signals that are used for territorial defense, social stability, and as a bonding mechanism. In previous studies, limited literature on seasonality in [ C. lupus ] howling is inconsistent (McIntyre et al., 2017). Some studies confirm a peak in howling during mating season (January April) while other studies have found evidence that howling is increased during non mating seasons. Therefore, in comparing fall data that was collected in 2018 to the spring data that would have been collected in 2020 this study would have further defined a seasonal howling pattern in C. lupus populations. A two night howling sound recording on a population of 25 diverse C. lupus and wolf dogs in captivity at Mission: Wolf sanctuary in Westcliffe, CO. was analyzed in this study. Such a small sample may not reflect the wild population due to pattern differences in sex, age, a limited number of potential breeding partners and social composition. Moreover, the recorded howls were emitted by a single [ C . lupus ] (solo howls) or by 2 or more howling successively or simultaneously (chorus howls) (Palacios et al., 2007). In this study, the seasonal mating cycle was considered in order to determine whether there will be an increase of howling patterns in the spring mating season in relation to the fall non mating season if C. lupus is in heat during the springtime. The object of this analysis could help biologists monitor wild populations of vocal animals like C. lupus through non invasive methods and properly inform administrators on the conservation strategies required ( Passilongo et al., 2015). Figure 1. Sum count of solo and chorus howl vocalizations on a non fed night vs. a fed night Figure 2 Dusk vs. Dawn comparison Initially , the study was done to establish a better understanding of the howling patterns of C. lupus spring mating season versus their fall non mating season. Due to the unforeseen circumstances of the COVID 19 outbreak in the spring of 2020, the complete study was unable to be conducted. In view of this, the existing sound recorded data from a previous fall 2018 study on howling behavior of C. lupus during a non feeding night versus on a feeding night under captive conditions was re analyzed. A fresh perspective on the sound recordings allowed for the potential to discover previously unnoticed howls and steered the study towards speculating what the possible outcome would have been if the spring data would have been collected. The howling results from both days showed an almost equivalent number of howls at 67 and 66 respectively ( Figure 1 ). Moreover, the ratio of the solo to chorus howls varied on both days. If the data were to have been collected during the spring mating season, it is theorized that the evidence would support the hypothesis for an increase in both howling frequency and solo and chorus howling patterns. There are many variables that may have had an impact on the results of the study. First, taking into account the reproduction rates of the C. lupus in captivity. Close quarters captivity of C. lupus may have a direct correlation to the reproductive rates. This could lead to a change in howling patterns since resources and mate availability are seemingly much higher in captivity in comparison to the wild. Research should be conducted on the reproductive rates of wild C. lupus, and comparisons made to determine the effects of captivity on mating. Additionally, the sample size of C. lupus changed from a population of 25 captive C. lupus in 2018 to a population of 24 captive C. lupus in 2020. This shift in population, however, would most likely not have any significant impact on the results acquired. Although, the addition or loss of new C. lupus may alter the currently established hierarchies and behavioral patterns ( Cafazzo et al., 2016). Thirdly, gender was not a variable that was recorded in the study but may have added a greater understanding of the howling patterns observed. The literature on the relationship between dominance and howling pattern comparisons between sexes is limited. Future studies may focus on this concept and provide further clarification of any relationship between howling patterns and sex. Furthermore, due to the study being conducted on a diversified sample of full bred C. lupus and hybrid wolf dogs, there is an unknown variable that the howling dynamic might differ between the two breeds howling patterns. Further studies must be done to determine the howling pattern between a purebred C. lupus and a wolf dog. Lastly, note that the previous study was done to determine a relationship between howling patterns of C. lupus on a non fed night and on a fed night. Feeding day could be a contributing factor to a decrease of howling due to full bellies. When repeating the study, the independent variables must be taken into consideration to provide accurate results. Limitations were involved during the recording and interpretation of the howling data. Since the recording and cataloging of data was done manually by each group member there was a large chance for human error. The duration and categorization of howls remained subjective where it was solely reliant on the listener to determine the proper analysis. Moreover, although the microphone was said to have the ability to minimize the sound of the wind, background noise still interfered with the recordings. The interference potentially muffled howls leading to an inaccurate interpretation of data. Future research may include recording data from multiple years of C. lupus spring mating and fall non mating seasons. This would also exclude the introduction or loss of new C. lupus into the sanctuary to provide more accurate results. The same data could also be re analyzed to determine which sex howled at each time and integrated into the study. Altamirano, D., Flores, J., Nguyen, K., & Pérez K. (2018). Wolf Howls: Effects of Feeding on Canis Lupus Howling Patterns. Unpublished manuscript, Metropolitan State University of Denver. Cafazzo , S., Lazzaroni , M., & Marshall Pescini , S. (2016). Dominance relationships in a family pack of captive arctic wolves (Canis lupus arctos ): the influence of competition for food, age and sex. PeerJ , 4, e2707. https:// /10.7717/peerj.2707 McIntyre R, Theberge JB, Theberge MT, Smith DW. Behavioral and ecological implications of seasonal variation in the frequency of daytime howling by Yellowstone wolves. Journal of Mammalogy . 2017;98(3):827 834. doi:10.1093/ jmammal /gyx034 Palacios V, Font E, Márquez R. Iberian Wolf Howls: Acoustic Structure, Individual Variation, and a Comparison with North American Populations. Journal of Mammalogy . 2007;88(3):606 613. doi:10.1644/06 mamm a 151r1.1 Passilongo , D., Mattioli , L., Bassi , E., Szabo , L., & Apollonio , M. (2015). Visualizing sound: counting wolves by using a spectral view of the chorus howling. Frontiers in Zoology, 12(1). doi : 10.1186/s12983 015 0114 0 Wolf. ( n.d. ). Retrieved April 2020, from https:// / Literature Cited