1. I was shocked when our tour guide said this was probably one of the only places in America where one can view elephant seals in their natural habitat. It was definitely a unique experience, as I am used to going to the zoo and having a piece of glass separating the animals and I. Yet, this was much more real and I liked how I could watch these animals in their natural habitat. They didn’t have to be kidnaped from their homes, making me feel good about the experience in general. I was glad to know that nothing major in an ecological sense had to be disturbed so that I could view these animals. I liked how close I was able to get to the animals, we were only twenty five feet away from the elephant seals. This was ultimately my favorite part of the experience. I have lived in California for my whole life, and this was the first time I have ever seen an elephant seal in person. The trip in general made me realize how little I know about the nature around me, and that I have so much more left to experience.
2. I thought that it was interesting when the guide said most male seals will merely lift their upper body and keep calling out their “name” to scare away other male competitors. Our guide said it was to conserve energy, yet a few times we did witness fighting. For such big creatures I found their agility to be amazing. As two male seals would begin to fight, they would lunge for each others necks very quickly. Moreover, the adult male barks were very deep and odd sounding; unlike anything I’ve heard before. However, the young pups sounded surprisingly like monkeys.
3a. While at Ano Nuevo Park, the guide discussed the migration patterns of elephant seals. She referenced a diagram that exemplified how male and female elephant seals have different migration routes. Scientists describe the path elephant seals take as being circular, and also believe this implies elephant seals have a specific destination in mind (Brillinger and others 1999). Moreover, before leaving for sea males attempt to mate again. Females leaving the beach must be very cautious while they exit, as males will attempt to mate with them. We are unsure what guides elephants seals along their journey, we speculate that cosmic forces may guide these animals based off of studies done on other large marine mammals (Vignieri 2018). Today, scientists believe that the migration pattern of elephant seals are being slightly altered. They hypothesize that the population of seals in Baja California is declining because they will not travel farther south due to climate change (García-Aguilar and others 2018).
3b. Elephant Seals were nearly hunted to extinction in the early 19th century as discussed at the park. It is thought that there were only ten to twenty elephant seals left (Hoelzel 1999). The populations became so low, people realized that elephant seals would not be able to survive on their own. As a result, laws were enacted in order to preserve the elephant seal population; they prevented hunting (Stewart and others 1994). However, a small population of elephant seals was found on Isla de Guadalupe. Thus, prompting the Mexican government to make Isla de Guadalupe a reserve, granting protection to these elephant seals (Stewart and others 1994). Further on, reserves such as Ano Nuevo provide elephant seals with a safe space to reproduce. Yet, it is important to note that even though conservation efforts were moderately successful, genetic diversity in the species is greatly lacking due to this bottleneck (also touched upon in the tour). Today, populations are increasing depending on where they are situated as some studies have found. As temperatures increase so will the the amount of elephant seals in the Channel Islands, however the elephant seal population in Baja California will probably decrease (García-Aguilar and others 2018). Thus, this indicates that the elephant seal population is not as stable as we would like to think. Under these environment scenarios, it is possible that the Baja California colonies will continue to decrease in the future, while the Channel Islands colonies will continue to grow.
3c. Summary of:Northern Elephant Seals Memorize the Rhythm and Timbre of Their Rivals’ Voices
This journal article divulges deeper into the significance of the elephant seal calls we heard at Ano Nuevo. As discussed at the park, there are alpha males and beta males. The article denotes how elephant seals begin to learn each others call using sound pulses and timbre (Mathevon and others 2017). The pulse rate is simply the number of beats over a certain amount of time. When a beta male hears the call of an alpha, he will back down. This elephant seal has associated this call with a superior competitor that he cannot beat. The elephant seal is the first animal to use sound in a biological manner, as this plays a large role in mating habits. (Mathevon and others 2017). In order to obtain this data, scientists utilized recordings to establish a relationship between recognition and the pulse rate of the call. This method supports the notion that elephant seals will not respond to a call that they do not recall, thus if they do not recognize the call they will in theory not recognize the individual. (Mathevon and others 2017).
Bibliography
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