Climate Change

Climate Change

Graph showing increased precipitation as we move into the future courtesy
of Littell et al 2009

Climate change is a problem that all species on the planet are currently facing, or will be facing, and is one that has a myriad of detrimental effects on the tufted puffin. Climate change is the result of increasingly large amounts of carbon dioxide being present in the atmosphere as a result of humans burning fossil fuels and changing the way that land is utilized. This release of carbon dioxide into the atmosphere has many negative effects on the environment such as global average air and water temperature rise, increasing ocean acidification, sea level rise, and changing precipitation patterns, all of which directly impact the tufted puffin. It's affected by these side effects of climate change in ways such as disruption of their food web and destruction and modification of their habitat. Increased precipitation in particular has, and is going to have, an effect on tufted puffin population numbers, as overall precipitation in the Pacific Northwest is expected to increase as we move into the future, and the occurrences of heavy precipitation events are also supposed to increase which is a double whammy of bad news for tufted puffins (Littell et al 2009). One reason this is bad news for them is because this will cause tufted puffins to delay egg-laying as they do not lay their eggs until their burrows completely dry out (Wehle 1983), and if their burrows never dry out then they will never lay their eggs, which becomes more and more of a possibility as we move into the future and it becomes wetter and wetter. Another reason this is bad news for them is because the increased precipitation will also inevitably lead to burrow flooding which harms chicks and causes burrows to collapse. In this way, climate change can directly cause another issue that tufted puffins must face, habitat loss and fragmentation. Another huge problem that tufted puffins must deal with is increased ocean water temperature. Ocean water temperatures have been increasing over the past century and are expected to increase even more as we move into the future. This situation does not create a particularly good scenario for the tufted puffin, as the increase in the water temperature will cause less food to be available to them as their prey species are mainly small marine animals, such as small fish and invertebrates, which are found in higher abundance in colder water which tends to be more nutrient-rich. Thus, if the tufted puffin isn't able to secure the amount of food that it requires than it's breeding success will be, and is, affected. The increase in sea surface temperature is also related to a decrease in breeding productivity in other ways, such as through the changing of timing of upwelling in the ocean. Upwelling is the movement of cooler, more nutrient-rich water towards the surface to replace the warmer, nutrient-depleted water that resides there. It is critical to tufted puffins because it contains much of their diet that they require for successful breeding. As it stands, the timing of upwelling is shifting to later in the year for a shorter amount of time (Bograd et al 2009), and tufted puffins have been shifting the times that they breed to earlier in the year, as their mean egg-hatching date has changed from July 15 to between June 22-July 10 (Gjerdrum et al 2003). This widening gap between the breeding season of the puffin and the timing of upwelling is going to continue exasperating the puffin's fledgling success problems. There is also evidence to suggest that overall increased sea surface temperature is directly linked to decreased fledgling success as seen in the graph below. In years where breeding season sea surface temperature was highest, the percent fledgling success of the tufted puffin was lowest. Overall, climate change and its effects in the form of increased precipitation and the rise of global average ocean temperatures are two major factors affecting tufted puffin populations in the Pacific Northwest.

Tufted puffin fledgling success as a function of breeding season sea surface temperature
from a study done on Triangle Island, British Columbia (Gjerdrum et al 2003)