TORONTO -- With the United States' land border still closed to non-essential travel, experts say some Canadian snowbirds may be staying home for a second consecutive winter.

Oct. 21 is the deadline for the U.S. Department of Homeland Security to declare whether it plans to ease these travel restrictions at the Canada-U.S. land border, or extend the prohibition for another 30 days.

No one knows for sure why the U.S. has kept the land border closed while Canadians can still fly into the country by air, but Toronto travel insurance broker Martin Firestone says he is telling his clients to have faith that it will reopen come October.

"There's going to be thousands and thousands of snowbirds that will for a second year in a row not find their way down south if it doesn't because it's going to curtail the season once again," Firestone told CTV News Channel on Wednesday.

As more Americans and Canadians get vaccinated, the Canadian Snowbirds Association (CSA) says it is hopeful the vast majority of snowbirds will be able to travel south this winter.

Evan Rachkovsky, a spokesperson for the CSA, told in an email that Canadian snowbirds are itching to return to the U.S., but the current ban is hampering their plans once again.

"As over 70 per cent of Canadian snowbirds travel to the United States in their Canadian vehicles, the ongoing closure of the U.S. land border continues to cause frustration amongst these travellers," Rachkovsky said Wednesday.

He added that snowbirds who live in their RVs year round are particularly impacted since most Canadian campgrounds and RV sites are closed during the winter months.

"The CSA is calling on the Biden Administration to lift the current restrictions at the land border as the Canadian government did for fully vaccinated American travellers earlier this year," Rachkovsky said.

The Canadian government eased travel restriction for U.S. citizens and permanent residents fully immunized against COVID-19 on Aug. 9.

The Biden administration announced in September that most adult foreign nationals will have to be fully vaccinated against COVID-19 in order to travel to the United States by early November. However, there were no details provided on how this new policy would specifically impact travel at the land border.

Homeland Security Sec. Alejandro Mayorkas previously said during a National Press Club event in Washington that the U.S. had hoped to ease land travel restrictions sooner, but the Delta variant delayed those plans.

If the land border remains closed come Oct. 21, Firestone said Canadian snowbirds do have some options, "all of which are expensive."

Firestone says older travellers typically want a vehicle at their disposal or an RV while in the U.S., and prefer to avoid the hassle of air travel, particularly since Canada's decision to allow fully-vaccinated visitors has dramatically slowed the customs clearance process.

"Why two people from the same family packing up their car and heading south across the border is not considered safer than going into an airport terminal with a thousand other peopleā€¦ is beyond any understanding," Firestone said.

However, Firestone said the cost of shipping a vehicle or an RV separately while paying for plane tickets is too expensive for most snowbirds. In addition, a shortage of available rental cars across North America has put a further premium on being able to take one's own car.

He says those who can't afford these options will likely remain in Canada for the winter season.

"Yes there are choices, but I don't think any [snowbirds] will take advantage of them if they need to have to do that," Firestone said.

A group of U.S. Senate Democrats, including Michigan senators Debbie Stabenow and Gary Peters, Sen. Kirsten Gillebrand of New York and New Hampshire Sen. Jeanne Shaheen, wrote a letter to U.S. President Joe Biden in September asking him to finally lift the travel ban.

"We believe that fully vaccinated Canadians should be allowed to safely travel into the United States via land ports of entry," reads the letter, which was also signed by New Hampshire Sen. Maggie Hassan and Minnesota Sen. Amy Klobuchar.

"We urge you to lift these restrictions before October, provide a plan for reopening land ports of entry and appoint an interagency lead on U.S.-Canadian border restrictions related to the COVID-19 pandemic," the senators said in the letter.

Firestone says the U.S. may be looking to open its northern and southern borders at the same time, however, the ongoing immigration crisis at the U.S.-Mexico border may be making the White House wary about easing travel restrictions altogether.

"I suspect that [America] wants an open border between their north and southern countries with respect to opening it simultaneously," he said.

With files from The Canadian Press