Chimpanzee

Our closest cousin, the chimpanzee (Pan troglodytes) is currently classed as endangered under the IUCN with it estimated to consist of a population of between 172,700 to 299,700 chimpanzees remaining. Chimpanzees have already gone domestically extinct in 4 countries already and are put under serious pressure in all other countries they reside in. 

This population has displayed an exponential decline with a report coming from the American Journal of Primatology (2017) which had predicted there to be an 80.2% decline within the last 25 years. More recent studies have said that great apes are in less danger than previously thought. Although, chimpanzees are in a better position, they are still seriously vulnerable and this will provide us with greater opportunity to prevent the extinction of this species. The largest  survey of great apes had inferred there to have been a fifth decrease in chimpanzees between 2005-2013.

Great apes are seriously vulnerable to decrease in population as they are classed as a type I in the survivorship curve which means they have very few natural predators and so will have a slow reproductive rate and prolonged maternal care. These species are highly vulnerable to this decline as they aren't capable of replenishing their population. 

This reduced population of chimpanzees are a by-product of habitat loss, degradation, commercialization of bushmeat and being infected by various fatal diseases such as ebola. Logging is a serious factor for this decline.

Morgan and Sanz (2007) had stated logging causes the loss of their food source, habitat and creates disruptions. This is especially evident in clear cutting logging. 

Studies on selective logging has been undertaken on the effects it creates on the great apes. It was discovered that most gorillas displayed positive responses to selective logging, however, the chimpanzee were significant more vulnerable. Positive effects are a result from increased light that can reach the forest floor and there is a strong correlation between the amount of sunlight the forest floor receives and the abundance/ diversity of the floral composition providing a greater food source prior to the logging. Although, chimpanzees more commonly responded negatively to all logging events there was rare occasions they displayed positive responses.

It is hypothesized that this decline response is because of the chimpanzee's territorial behaviour to one another. When logging begins, the chimpanzees will feel unsafe in their territory they will migrate which is likely to force them to enter a different clan's  territory. This will then lead to brutal fighting between the chimpanzee's clans.

References
Gaworecki, M., 2017. Western Chimpanzee Numbers Declined By More Than 80 Percent Over The Past Quarter Century. [online] Mongabay Environmental News. Available at: <https://news.mongabay.com/2017/07/western-chimpanzee-numbers-declined-by-more-than-80-percent-over-the-past-quarter-century/> [Accessed 22 July 2020].

  World Wildlife Fund. 2020. Chimpanzees | Species | WWF. [online] Available at: <https://www.worldwildlife.org/species/chimpanzee> [Accessed 22 July 2020].

World Wildlife Fund. 2020. Largest Ever Study Of Gorillas And Chimpanzees Finds More Than Expected | Stories | WWF. [online] Available at: <https://www.worldwildlife.org/stories/largest-ever-study-of-gorillas-and-chimpanzees-finds-more-than-expected> [Accessed 22 July 2020].

Aardvark daytime activities detrimental to species

Researchers of the University of the Witwatersrand (UW) have examined the reasons for why aardvarks are now active during the day and how this may be detrimental to the population. This daytime wandering is becoming a regular occurrence in dry southern African countries. 

UW had worked in conjunction with the University of Cape Town and the University of Petoria to better understand what the change from nighttime to daytime active periods means for the species. Studies were performed on the aardvark population in Tswalu where body temperatures and activity periods were monitored across a 3 year period. Dr Nora Weyer completed her PhD research on this nocturnal animal using satellites in conjunction with the monitoring of this population's body temperature and activity period. 

After this study, it was confirmed that the hypothesis formed prior to the survey had been accepted. It was confirmed that the drought's that have recently become more frequent are the reason for this shift. Drought's are responsible for the death of many vegetation within this arid region which then remove a major food source for the aardvark (ant & termites). The aardvark changed their active periods from night to day so they can better conserve their energy by not having to increase their body temperature in the colder nights especially during drought periods where they don't obtain a sufficient energy source.

During the study 5 out of 6 aardvarks being monitored had died because of these unhospitable conditions. The aardvark acts as an ecosystem engineer as they provide shelter for many organisms incapable of burrowing which will create detrimental effect onto this vulnerable, unique ecosystem.

Aardvarks have been able to cope in the past with these harsh arid conditions, however, based on previous studies it is predicted that these droughts will be too much for these populations to handle.

• Yirka, B., 2017. Study Suggests Climate Change May Kill Off The Aardvark In Some Areas. [online] Phys.org. Available at: <https://phys.org/news/2017-07-climate-aardvark-areas.html> [Accessed 20 July 2020].
• ScienceDaily. 2020. Daytime Aardvark Sightings Are A Sign Of Troubled Times: Wits Researchers Find That Aardvarks Feeding In The Daytime During Droughts Might Be Starving. [online] Available at: <https://www.sciencedaily.com/releases/2020/07/200709092459.htm> [Accessed 20 July 2020].

Are cukoo's the new dodo bird?

The Bristosh cuckoo population has displayed a 71% decline within the previous 25 years. This decline has been a mystery to many until monitoring was recently taken place. Tracking devices were attached to 42 male cuckoo birds prior to their migration. This survey had discovered that these birds have 2 migratory routes. One route goes from Britain to the African continent via Spain and another where they bypass Italy. Those who flew threw Italy ( a longer route) had a significantly lower mortality rate upon their return to Britain/ Ireland. It was noted that the majority of deaths had occurred prior to reaching the continent of Africa and so it is hypothesized the decline is primarily yet another result of climate change. 

Spain have suffered from severe droughts and fires meaning there will be less water source. More time had been spent in breeding sites for those bypassing Italy with it being expected to be because they're developing a greater deal of pre migratory fattening. Due to this lack of precipitation there is also a decrease in vegetation growth that makes up most of the caterpillar/ moth's diet. This is significant as the caterpillar and moths are the major food source for the cuckoo bird. This lack of food source and water availability will then quite obviously cause death especially during a harsh migratory route. 

Spring migration is commonly associated with energy selected migration and Spring migration is related to time selected migration. There are currently issues on the timing of Spring migration due to the incompatible breeding resources available where the hosts nests are located where the cuckoo wishes to lay leading to an exploitative interaction.

https://en.wikipedia.org/wiki/File:Cacomantis_flabelliformis.jpg

References

•  Briggs, H., 2016. Cuckoo Decline Finally Mapped. [online] BBC News. Available at: <https://www.bbc.com/news/av/science-environment-36837641/cuckoo-decline-finally-mapped> [Accessed 11 July 2020].
•  Hewson, C., Thorup, K., Pearce-Higgins, J. and Atkinson, P., 2016. Population decline is linked to migration route in the Common Cuckoo. Nature Communications, 7(1).