Solutions for Act I Scene 2 - Chains

While the image initially looks like a food chain diagram, a few properties seem to imply it doesn't describe any set of animals' diets. Most arrows point downwards, which is uncharacteristic and unlikely given the environmental clues, since the arrowhead tends to point to the predator in these diagrams. The title also suggests we care more about individual chains between pairs of animals than the whole web itself.

Using the background image, which implies the (very general) natural habitat of the various featured animals, along with the number of dashes for each position, a few animals can be narrowed down fairly quickly. For example, the first missing animal, being in the air and four letters long, is likely a BIRD.

The leap to make here is to realise that what the arrows actually represent are compound-word/phrase connections (which create other animals). For example, the BULL points to DOG, FROG, SNAKE, and SHARK, because there are animals that are commonly named bulldog, bullfrog, bull-snake, and bullshark. All featured chains should be commonly recognisable or easily checkable.

With this information the spaces can all be filled out to look like this:

The red letters can be read left-right, top-bottom to spell out BINTURONG PAIRING. A new pair of animals that is a nickname for the binturong is bearcat.

Design notes:
This puzzle idea had been floating around for a while before being used this year, mostly because it was hard to guarantee solvability and completeness. Providing even one animal's name made the puzzle a lot easier/less fun to solve, so in the end the "environmental" clues were provided in place of this.

Solvers could probably guess that if the food web were to cover every possible pairing with arrows, the image would be a lot more complicated. It seems there are many animal pairings that are considered allowable by zoologists, from "cat squirrel" to "spiderfish" (or really pretty much anything-fish, or -shark). The decision was made early on to not intend including all possible arrows, because it could lead to more confusion than if all were included. Essentially, even if someone knows what a squirrelfish is (for example), they should be less worried that no arrows exists for this pairing than someone who doesn't know about squirrelfish and can't justify an arrow between those two animals. So in general, we opted to use arrows only when the pairing was a commonly-known one (as judged by number of dictionary entries and/or Google search results), using less-common animals only when required to uniquely identify a space.

The answer is: bearcat