Bail Jumper will stay in New York rather than travel to Bowie and be favored in Saturday's $58,800 Marylander Handicap. "His owner and trainer don't want to ship him down in the heat," is the official explanation.

Increasingly, the prolonged, stretch of high temperatures and heavy humidity is having its effect on East Coast racing. Horses are by nature cold-weather animals. Given a choice, they would rather run at Bowie in February than in July.

"We try to help them out in weather like this," trainer Tommy Field said yesterday in Queenstown, a section of the Bowie backstetch where a tree - any tree that could provide a little shade - is a 100-to-1 shot.

"Some trainers set up special fans through their barns," Field observed. "We don't I have to think the fans do little more than move the hot air around. We keep all our doors open, our hay racks are hung right outside the stall door to encourage the horse to stick his head out, to pick up whatever breeze there may be coming through the pathway.But it's close.

"You have to compensate. I cut the workouts of my horses back from, say, a mile to three-quarters (of a mile). And I get them outside as often as possible so they get some fresh air. Any little exercise has to help."

Field is stabled in Barn F at Bowie. That is F for Fied, these days, becase the only element as warm as the weather in Eastern racing this month has been Tommy Field.

The former steeplechase jockey form Middleburg, Va., trains 40 horses for 15 owners. In less than a month, form June 18 through July 16. Field's public stable captured six stakes with four horses at four tracks.

When you're hot, you're hot, Field is sizzling.

Debby's Turn started the streak by winning the Seashore Stakes at Atlantic city. The champion Maryland-bred 2-year-old filly of 1976 then came back to take the Queen Anne Handicap against older rivals at Bowie the next weekend.

On July 4 Tiny Monk scored in the Penn Treaty Stakes at Keystone. Regound got home first that same holiday afternoon in the Fort McHenry Handicapped Bowie.

Two weeks ago Turn The Guns won the Lady Baltimore Handicap here. On Saturday Debby's Turn registered in the second division of the Open Fire Stakes on the grass at Delaware Park.

Saturday, Field will saddle Sea Defier in the Marylander.

"It's been a case of everything breaking just right," the trainer remarked. "I have had times, like everyone else, when I sent out the best horse and lost. Right now everything seems to have been set up right.

"Debby's Turn, of course, is an exceptional filly. She can be a little moddy at times but any trainer would be happy to put with her. She has won nine stakes at seven different tracks from five-eighths to a mile and a sixteenth, including one under the lights at Atlantic City and one where she was on grass for the first time.

"Tiny Monk is, well, tiny - but very game. Resound is going to make a good stud. Turn The Guns is by Turn To Mars, like Debby's Turn and Coral Dawn, who ran a good second to Gala Lil here Wednesday."

The obscure stallion Turn To Mars thus been greatly responsible for much of Field's sensational summer.

"He stood at a farm near Ohstrom, Va., Field said. "Now he's in Kentucky, I had three seasons with him. Turn To Mars didn't stand training but he was an exceptionally fast horse."

Whether Field can add to his streak Saturday is questionable.

"I entered Sea Defier just to take a look, to see who mihgt be coming down for the race from New York," Field said. "At 103 pounds, (Robert) Lillis is able to make the weight. I'll rid him."

In addition to Bail Jumper, For The Moment and Affiliate will skip the Marylander, Bowie's closing-day feature. This left Counter Punch and Pruneplum the starting high weights, under 114 pounds, when the field of nine was drawn yesterday morning. Completing the lineup for the nine-furlong event are Courtly Haste. 112 pounds: Get The Axe, 112: Pefect Motion, 106; sparkling Fellow, 112: Lynn Davis 112; and Command Point, 111.