My apologies for the delayed blog post from last week, a few technical difficulties, but here it is!
Some of us may find munching on a slippery sea vegetable less desirable than say a slice of oven fresh pizza topped with cheese, chicken and onions, or even repulsive, but sea snails certainly don’t mind one bit! It has yet to be determined whether sea snails would prefer pizza if given the opportunity to graze on the cheesy substrate but I guess we’ll have to leave that for another time, perhaps for my independent project. OK back to the important stuff, this lab experiment was conducted to examine the effects of variable temperatures on herbivory. Herbivory is an important aspect of marine ecosystems because primary producers such as kelp that are being grazed down by munch happy herbivores are important in their ability to drive energy production via. photosynthesis at the base of the food chain. Temperature is an important factor to consider because it could potentially influence both primary producers and herbivores in ways that could upset the stability in the ecosystem. This becomes even more important when you put temperature change in the context of major scale changes in temperature caused by global warming.
In our experiment, our herbivore of interest was the black turban snail and our primary producer of interest was the bull kelp. For our experiment on snail feeding, we set up four feeding chambers in which two black turban snails had access to a healthy supply of bull kelp, while the other two chambers had no snails with kelp as a control. This setup was intended to last a week, however just two days into the experiment it was discovered that a majority of the kelp in the feeding chambers had DISSAPEARED (or was on the verge of disappearing). Hmm…I wonder where all that bull kelp could have ended up. Luckily, thanks to the valiant efforts of several volunteers and our TA, we were able to salvage what was left of the kelp so we could compile the data.
Black Turban Snail! (Cute little guy) A couple of female bulls (cows) casually munching on some bull kelp.
In the second half of our experiment we examined the effect of different temperatures on the black turban snail’s behavior such as biting rate, righting time and speed. We literally leaned our heads against the side of the glass tanks in which the snails were feeding, peering eagerly trying to get a glimpse of how fast their mouths were moving. Note: either they are being really polite eaters in front of strangers or their feeding behaviors are ridiculously hard to observe with the naked eye. For riding time we essential put them on their backs with their shell opening facing the glass tank and measured how long it would take for them to regain an upright position. Snails are surprisingly flexible creatures…if they put their mind to it. Finally we measured the snails speed. If there’s one takeaway from this lab other than the fact that it takes patience to develop a trusting and working relationship with snails in a lab setting, snails are intelligent creatures who play a major role in marine food chains which gives us more of a reason why we should care about their behavior and well being brought on by the effects of temperature change.
For an up close and personal view of a snail munching away to the delight of enthusiastic biologists (cue the music and the cheers)
or for more tidbits on the black turban snail