Scientists from the National Centers for Coastal Ocean Science Conducted

Multiple Choice

Scientists from The National Centers for Coastal Ocean Science conducted a 6-year study on the effects of ocean temperature change on abundance of dominant intertidal species (barnacles and mussels) . These organisms can outcompete other intertidal organisms for space (and therefore distribution and abundance) . Suppose the scientists collected the following data on average intertidal zone temperatures (C°) and densities of mussel clumps and barnacle colonies (per square meter) :
$$\begin{array} { | l | l | l | l | } \hline { \text { Year } } & \text { Avg. Annual Intertidal Zone } & & \\ & \text { Temperature } \left( \mathrm { C } ^ { \circ } \right) & \text { \# Clumps Mussels/sq m } & \text { \# Colonies Barnacles/sq m } \\\hline 2004 & 6 ^ { \circ } & 6 & 22 \\\hline 2005 & 6.7 ^ { \circ } & 5.5 & 19 \\\hline 2006 & 7.3 ^ { \circ } & 5 & 17 \\\hline 2007 & 7.8 ^ { \circ } & 4.75 & 16.5 \\\hline 2008 & 8.2 ^ { \circ } & 4.5 & 16 \\\hline 2009 & 8.5 ^ { \circ } & 4.5 & 16 \\\hline 2010 & 8.7 ^ { \circ } & 4.5 & 16 \\\hline\end{array}$$
-What can the scientists conclude from the data?

A) An increase of 2.2°C from 2004 to 2008 reduces the density of barnacles and mussels by approximately 25%.
B) An increase of 6°C is needed before the number of clumps of mussels decreases.
C) Increasing annual ocean temperatures do not affect abundance of mussels or barnacles.
D) If annual ocean temperatures were recorded for another three years, scientists would likely observe steady temperatures.