CITY FISH, COUNTRY FISH: HOW FISH ADAPT TO TROPICAL SEAS AND COLD OCEANS

Award-winning South Portland author Mary Cerullo is back, with another excellent nonfiction book about ocean life, this time explaining the magnificent differences between fish in the tropics and the cold oceans.

Cerullo has published more than 20 books about ocean creatures like sharks, octopuses and giant squids. Here, she teams up with acclaimed underwater photographer Jeff Rotman for this latest volume in Tilbury House’s “How Nature Works” series.

Cerullo’s clever title is a smart way to introduce the earth’s ocean bioregions, especially fish adaptation to warm tropical waters and cold ocean waters far from the equator. She describes the tropical habitat of a coral reef as a densely populated “city” of high-rise condos — busy, crowded, colorful, attracting thousands of species of plant and animal life. The cold ocean, however, is the “country,” wide open, less densely populated, with fewer varieties of fish, but also described as a “giant food factory.”

She also explains that warm tropical seas produced brightly colored fish whose vivid rainbow colors mean either a welcome or a warning. Cold-ocean fish are typically colored with earth tones (gray, black, brown) as camouflage to fool predators, often swimming in large schools for defense.

With Rotman’s stunningly beautiful underwater photographs, Cerullo tells about the specialization of tropical fish, like special mouths for feeding and hidden weapons like the surgeonfish’s scalpel-like fins. Cold-ocean fish are noted for their strength and stamina.

She also points out how and why the oceans are changing, with global warming and acidification, and why humans should remember they are visitors to the ocean, but it’s the fishes’ home.

Learn why night is just as busy as day underwater, why a tropical sea appears to be blue, but a cold ocean looks green, and what an ichthyologist really does.

MAPPING MURDER

“The worst thing about history is that any time it repeats itself the price goes up,” said a wise pundit, especially when someone is willing to commit murder to obtain even a small piece of history. And the director of the Ryland Historical Society knows only too well the price of past history and present death.

“Mapping Murder” is Portland author William Andrews’ third mystery featuring erstwhile museum director Julie Williamson. This follows Julie’s two earlier mysteries, “Stealing History” and “Breaking Ground.”

Although billed as a “historical whodunit,” it really is a present-day murder mystery involving valuable historical artifacts, a nice suspenseful combination of past and present with more than a few plot twists and surprising revelations.

Julie has been the director of the Ryland Historical Society (and museum) for five years, and is considered to be an expert on museum security. So, when several other directors of Maine museums seek her advice about missing artifacts, Julie’s interest is aroused.

She thinks the artifacts are not missing, but stolen, and cannot understand how or why. Old maps, ceramics and an obscure painting have disappeared from various museums, but there is no pattern, no clue. More puzzling, however, is why the affected museum directors have not notified the police.

Then, when one colleague is murdered after talking with Julie, she and a savvy state police detective discover a long list of suspects but no motive link. Are the thefts and the murder random, connected or part of something bigger? Julie sets several clever traps, but puts herself in danger as a target, too.

This is a complex story with plenty of suspicious characters and loads of historical references, clues, red herrings and insight into museum and historical society operations and vulnerabilities.

Bill Bushnell lives and writes in Harpswell.