Critique of the Introduction
The introductory part of the article has both strong and weak sides. The strong side of the introduction is that it points out the significance of the research and summarizes previous scientific works related to the issue discussed. All the necessary background information the reader might know in order to understand the meaning of the research is provided – the mechanism of adrenocortical stress response is explained very clearly, short and long-term effects of animal stress and the method of studying the variations of stress response is also briefly presented.
However, weak side of the introduction is that it lacks consistency in certain parts. For example, the hypothesis is not stated clearly. Furthermore, the authors seem to repeat themselves at certain points and the introduction might have been written in more concise and structured format.
Critique of the Methods
The study system is the Magellanic Penguin colony at Punta Tombo, Argentina. The researchers imply several scientific methods, namely capture stress and behavioral response protocols, radioimmunoassay for corticosterone, and statistical analysis to test whether there is a difference between corticosterone responses in visited and undisturbed chicks. An interdisciplinary approach allowed the researchers to get more accurate and broader picture of the issue the experiment was not limited to one technique and researchers have used several methods in identifying the factors causing stress. Thus, the researchers have managed to collect different information only in one experiment the stress caused by human intrusion into penguin existence has been minimized.
Moreover, the methods used are described in detail, so a person who has relevant equipment and experience can carry out the experiment using the instructions from the article. This system is well-suited for examining the hypothesis. Chicks were examined in the same colony, yet in different parts of it. The researchers could see a clear distinction between visited and undisturbed chicks. Because of the chick nests territorial proximity, alternative factors could hardly interfere with the experiment. The only shortcoming was the small number of chicks examined. Only 7 chicks from each area were studied only 14 chicks were considered for the research and such a small number can show the incomplete picture. Some of the information presented in the method section should be moved to the introduction part because it does not deal with the method at all. For example, the description of where penguins spend the winter and how many eggs they lay down has no relevance to Methods section.
Critique of Results
The findings presented in the Results section describe the statistical data that includes body mass, size and condition for Magellanic penguin chicks, and the comparison of baseline and integrated levels of corticosterone between tourist-visited undisturbed chicks. The obtained results are illustrated by two corresponding figures. However, the results are not clear enough. In addition, the findings are overloaded by indices and values. The overall presentation of the data is very specific it is not difficult to comprehend the information. Figure 1 does not prove that human influence causes stress in chicks and has a negative impact on penguins.
Critique of Conclusion and Personal Comments
The conclusions made by the authors are rather informative, though some of the results appeared to be surprising and unexplained. The authors do not give clear explanation concerning what causes robust stress response expressed by hatchlings in the areas visited by tourists, and why young chicks perceive the presence of humans when adults show little response to people. The results of the study have implications for further research, as the study is concerned with the impact of anthropogenic disturbances on wildlife. It is now obvious that seabirds in undisturbed areas respond on humans differently than in tourist-visited areas. However, the differences have been also noticed in different age groups of penguins living in the same area. The authors emphasized the need to conduct further research in order to identify the factors which might be stressful to organisms. The article provides the readers with statistical material; however, it does not explain the obtained results. That is why it doesn’t help to advance theory in wild nature preservation.
It is impossible to generalize the results of the research and the further investigation is required to prove and explain why penguins of different ages living in distinct areas express various stress responses. In the discussion section the authors compare the results obtained in this case to those obtained by other researchers earlier. It is especially interesting to note the differences in reaction of newly hatched chicks and their production of corticosterone in different areas. The results of the article have large implications on conservation of penguins, because the interaction with humans can influence the health of the penguins in a negative way.
Though the article in general is well-written and organized in a clear manner, it is difficult to understand the information provided due the excessive usage of figures and specific terms. The article is interesting to read and is not limited to specific audience the school students as well as biologists are able to find something in this research. The article addresses the issue of wild-life preservation which is a hot topic today and the authors have provided an insight on one of the problems the stress humans can cause to penguins. The results discussed in the article can become the guideline on how to protect not only penguins but other birds and animals.