Author: routte.11

New Zealand Tourism Consequences on Yellow-eyed Penguins

Yellow-eyed penguins at Katiki Point in New Zealand. Photo taken by Iain McGregor. Retrieved from https://www.stuff.co.nz/environment/105577298/people-with-selfie-sticks-are-harming-endangered-yelloweyed-penguins

 

The yellow-eyed penguin is endemic to New Zealand and is also a popular cultural icon in New Zealand (Katz, 2017). However, over the years these penguins have faced population declines and are now considered to be endangered. Human disturbance has a large impact on the population of yellow-eyed penguins. A large cause of population declines comes from unregulated tourism (McClung et al., 2004). Since these penguins do not have many habituation opportunities, they are more sensitive to human tourism (French et al., 2018).

Tourism impacts stress, reproduction, and behavior in yellow-eyed penguins (Ellenberg et al., 2007). The presence of humans around these penguins causes an increase in stress-induced corticosterone. If this stress is prolonged or frequent, it can result in decreased fitness and survival in adults (Ellenberg et al., 2007). This increased stress can also impact the behavior of adults and their reproductive success (French et al., 2018).

Tourists often will ignore fences and signs in order to get closer to the penguins (Huffadine, 2018). Penguins in these touristed areas have lower breeding success and lower fledgling weights (McClung et al., 2004). A large reason for this is that the presence of tourism will cause the stressed penguins to change their behavior to avoid the humans. These changes in behavior include a decrease in the time spent at their nest, an increase in travel time, and an increase in the likelihood of nest abandonment (French et al., 2018). These changes in the behavior of adults cause negative impacts on the survival of their children.

Parental care is an important factor in the growth of fledglings. However, with the adult penguins spending more time avoiding the nests because of tourism, the fledglings receive lower provisions. Continuously missing meals or missing a meal during a year with poor food supply can lead to lighter fledgling weights and even death (Huffadine, 2018). Lower fledgling weight can have long-term population consequences like lower survival and recovery rates (McClung et al., 2004). It is important for humans to better mitigate the impacts of tourism in order to help protect this endangered species.

References:

Ellenberg U., Setiawan A. N., Cree A., Houston D. M., Seddon P. J. (2007) Elevated hormonal stress response and reduced reproductive output in Yellow-eyed penguins exposed to unregulated tourism. General and Comparative Endocrinology, 152(1):54-63.

French R., Muller C., Chilvers B.,  Battley P. (2019). Behavioural consequences of human disturbance on subantarctic Yellow-eyed Penguins Megadyptes antipodes. Bird Conservation International, 29(2), 277-290.

McClung M. R., Seddon P. J., Massaro M., Setiawan A.N. (2004) Nature-based tourism impacts on yellow-eyed penguins Megadyptes antipodes: does unregulated visitor access affect fledging weight and juvenile survival?, Biological Conservation, 119(2):279-285.

Katz B. (2017) New Zealand’s Yellow-Eyed Penguins May Be in Trouble. https://www.smithsonianmag.com/smart-news/new-zealands-yellow-eyed-penguins-may-be-trouble-180963340/

Huffadine L. (2018) People with selfie sticks are harming endangered yellow-eyed penguins. https://www.stuff.co.nz/environment/105577298/people-with-selfie-sticks-are-harming-endangered-yelloweyed-penguins

Divorce in Black-browed Albatrosses

Two black-browed albatrosses. Photo taken by Francesco Ventura. Retrieved from Mclure, 2021: https://www.theguardian.com/environment/2021/nov/24/climate-crisis-pushes-albatross-divorce-rates-higher-study 

Black-browed albatrosses are monogamous birds that typically mate for life. These birds will spend a large portion of the year flying across the ocean and return to land for reproduction with their partner (Aridi, 2021). However, albatross divorce does occur and typically happens when the partners fail to reproduce. Unfortunately, as climate change has increased, so has the divorce rates among the black-browed albatrosses (McClure, 2021).

As global temperature increases with climate change, so does the temperature of the water. The warmer water temperature means a lower fish survival, which means that the albatross will have less food. The albatross will then have to travel farther to get food, thus spending more time and energy out at sea (McClure, 2021). The lower amount of food causes a less successful reproduction rate. The stress from searching farther for food creates the production of corticosterone, a stress hormone secreted in response to environmental triggers (Ventura et al., 2021).

Stress hormones are a big factor in the selection of mates for the reproduction process. Albatrosses produce one chick during the breeding season, so having the correct partner is vital for their reproduction (Aridi, 2021). When albatross spend more time searching to food, they can return late in the breeding season and in poorer health. This is likely to result in less successful breeding and more production of stress hormones (McClure, 2021). Female albatrosses have the ability to sense their physiological stress and mistakenly blame their stress on the performance of their male partner. Due to this partner blaming, the female albatross will sometimes divorce the male and search for a new mate (McClure, 2021).

A study by Ventura et al. (2021) found divorce rates average 3.7 percent. However, divorce rates reach 7.7 percent in 2017 when the highest the surface water temperature was observed. This means that albatrosses respond to higher water temperature by creating more stress hormones, which causes stress in relationships and leads to divorce. The black-browed albatross is a near threatened species, so climate change caused warming water increases divorce and makes the species more susceptible to population loss (Aridi, 2021).

References

  1. Ventura F, Granadeiro JP, Lukacs PM, Kuepfer A, Catry P. (2021) Environmental variability directly affects the prevalence of divorce in monogamous albatrosses. R. Soc. B. 288:20211212
  2. Aridi R. (2021) Albatrosses Mate for Life, but Climate Change Has Doubled Their ‘Divorce’ Rates. https://www.smithsonianmag.com/smart-news/climate-change-is-to-blame-for-albatrosses-rising-divorce-rates-180979143/ 
  3. McClure T. (2021) Climate crisis pushes albatross ‘divorce’ rates higher – study. https://www.theguardian.com/environment/2021/nov/24/climate-crisis-pushes-albatross-divorce-rates-higher-study