Wednesday, 28 March 2012

Don't bite the hand that feeds...


Hammerschlag, N., A.J. Gallagher, J. Wester, J. Luo, and J.S. Ault. 2012. Don’t bite the hand that feeds: assessing ecological impacts of provisioning ecotourism on an apex marine predator. Functional Ecology: 1-10.

Ecotourism is a responsible form of travel that combines involvement in environmental conservation, helping out the local community, and getting to experience a cool part of nature. As we learned in class, ecotourism is an essential part of conservation, as it provides the funds and involvement necessary to head conservation projects, that otherwise would not be as successful. However, some ecotourism practices could have a negative impact on conservation, disturbing the natural activities of the very animals it is trying to protect. For example, there are cases where food is used to attract wildlife for tourist viewing pleasure, such as the shark diving industry, where chum (fish parts and blood) is put into the water to bring sharks into the area around the divers.



There is much debate about whether this practice negatively impacts the normal behaviour and ecology of the sharks. Hammerschlag and colleagues (2012) decided to investigate this issue by using satellite telemetry to study the long range movement patterns of tiger sharks (Galeocerdo cuvier; the largest apex predator in tropical waters) in response to dive tourism. They looked at two separate populations of tiger sharks: one in Florida where shark feeding is illegal, and one in the Bahamas where this type of ecotourism is regularly used.  One might expect that shark feeding may make the sharks more reliant on that type of easy meal, and restrict how far they travel from that area. This could pose a threat to humans in the area, if the sharks associate humans with food, and it could also have ecological consequences by altering the normal diet and movement of the sharks. Yet, Hammerschlag and researchers’ results suggest that this is not the case. They found that there was no difference between the migration patterns and habitat use between the two populations.One reason they suggest to explain this is that tiger sharks are opportunistic foragers, so they go wherever there is the highest productivity of food.

Because this shark feeding practice does not seem to have a negative effect on the sharks, there seems to be no reason to stop it, as it brings in large amounts of money to help with the conservation efforts. However, some species may be more sensitive to human interference than others, so wildlife provisioning should not be used without thorough research of the possible impacts to the behaviour and ecology of the species.

Video summary of research: http://www.youtube.com/watch?v=9iFl7BxbnXQ

Word Count: 434

Wednesday, 14 March 2012

Falcons for Grapes


Kross, S.M, J. M. Tylianakis, and X.J. Nelson. 2011. Effects of introducing threatened falcons into vineyards on abundance of passeriformes and bird damage to grapes. Conservation Biology 26: 142-149. http://onlinelibrary.wiley.com/doi/10.1111/j.1523-1739.2011.01756.x/pdf

In their recent article published in Conservation Biology, Kross and researchers (2011) found a way that a threatened falcon species can benefit agriculture, while receiving protection. Vineyards are regularly raided by birds, such as Blackbirds (Turdus merula), Song Thrushes (Turdus philomelos), and Starlings (Sturnus vulgaris), which eat or cause damage to the grapes. When the threatened New Zealand Falcon (Falco novaeseelandiae) was introduced into the vineyard as part of a “Falcons for Grapes” conservation project, it effectively reduced the abundance of vineyard pests and decreased the number of grapes removed by a whopping 95%! The researchers calculated that the presence of falcons can potentially save the vineyard US$234/ha for the Sauvignon Blanc variety of grapes and $326/ha for Pinot Noir variety of grapes. These numbers should be enough to convince any vineyard owner to consider becoming involved in the protection of at-risk falcon species.



Previously, the methods used to scare away birds were just deterrents, like loud noises, which the birds could easily become accustomed to. But, with the new falcon approach, it costs less money to implement, and its effectiveness saves more money in the long run. Not to mention, that you are part of an important conservation effort that you can feel good about. Already, in places like Sonoma County, CA, where vineyards are a big business, falcons have been trained to chase away pesky birds (but not to eat them because that takes too long; Bussewitz, 2011).

The reason this paper caught my attention was because the Okanagon Valley in B.C. relies strongly on vineyards and wine production. It would be interesting to see if a program involving the protection of the Peregrine Falcon (Falco peregrinus; a species red-listed in B.C.) or other falcon species in the area would benefit from this sort of relationship. Kross and researchers paper was a very fitting way to wrap up what we have been talking about in class: Economics and conservation can go hand-in-hand after all! What a perfect example of conservation and agriculture working together to produce a positive outcome that benefits both parties.

Word Count: 390

Supplementary Info:
Bussewitz, C.  2011. Falcons guard Sonoma County vineyard. The Press Democrat: 1-2.