1) “Human Footprint,” 9 p.m., PBS. The notion of “biocontrol” — one part of nature controls another — can work well: In Thailand, 10,000 ducks are released to gobble up farm pests. And it can fail: In 1935, Australia brought cane toads (shown here) to stop beetles; they soon swarmed everywhere … just as rabbits did earlier. Like last week’s opener, this is a terrific hour.
2) “Sullivan’s Crossing,” 8 p.m., CW. Maggie is a former Boston surgeon, now at her dad’s Nova Scotia resort. This idyllic world is threatened by a developer, who’s now hospitalized. With good people (mostly) in great settings (always), this hour resolves many crises … then, in the last minute, starts a big one, setting up the season’s final two hours.
3) “Equalizer,” 10 p.m., CBS. Things rarely go smoothly for Robyn. She and Dante are on a romantic getaway when Salazar and his gang attack. Earlier in the night, CBS has “Hollywood Squares” reruns, now that “Raid the Cage” is done. “Big Brother” arrives next Wednesday.
4) “MasterChef” and “Secret Service,” 8 and 9 p.m., Fox. With viewers distracted as the Fourth of July nears, Fox retreats to reruns. “MasterChef” tells the duos to combine sweet and spicy elements; “Secret Service” repeats its opener, at a Greek restaurant in Washington, D.C.
5) ALSO: CW has pulled its “Children Ruin Everything” episodes, replacing them with a “Trivial Persuit” rerun. NBC’s “Chicago” reruns start at 8 with “Med”; Ripley tries to rescue a woman and her daughter, who are stuck in a well. “Fire” is at 9, with “P.D.” at 10: a street war endangers Atwater’s attempt to create a community-center.