Dear Reader,
I deplore missing dives I’ve paid for, especially when time is limited. The
  Nimrod Explorer’s advertised first day schedule is, “Lunch served on way to the
  first dive site; two dives are offered today, including the orientation dive, at
  Lagoon Reef.” So, to arrive at the boat by noon, I rose at 5:45AM, then got picked
  up for a bus trip to their 5-seat air charter, which flew to the vintage WWII
  landing field at Lockhart River; then a van to Portland Roads over an unpaved,
  washboard surface that’s impassible during heavy rain; and a short ride in an
  inflatable to the Nimrod. All for a long wait until 6:45PM for the reprovisioning
  and refueling barge to arrive. Two precious dives. Scrapped. A Scottish chap
  chimed in that the same happened on his trip last year. For the time and money I
  spent, I’d expect an operation to find a way to guarantee that first dive day.
But if the diving goes well, one soon forgets about such matters and after a
  few tours of the reef I had become one happy diver. The Nimrod Explorer departed
  Cairns for its remote Ocean Outback Adventure, eventually reaching Raine Island,
  in the Coral Sea. Only one other vessel, the Undersea Explorer, makes the journey.
  This section of the Coral Sea was ours alone.  
Marine life is mind-boggling. I saw more than twenty species of butterflyfish,
  from the eastern triangular to the Pacific double-saddle. Not to mention the
  hybrids from interspecies hanky-panky like the offspring of dot and dash and spotbanded
  varieties with their delightful arabesques and curlicues.  
The legendary visibility on the shallower reefs was only 40-50 feet due to
  coral spawning. At outer bommies of the Great Detached Reef, such as the phenomenal
  site called The Pinnacle, visibility hit 100 ft. and the dives as much as 120
  ft. In November, we had little current and the water hovered around 80ºF.
 The hard coral reefs, which rise to
inches below the surface, are pristine –-
certainly the healthiest and most colorful
I’ve seen. Except for a couple that
have suffered storm damage, most sites
have magnificent stands of branching corals
from large elkhorn to tiny, delicate
blue- and pink-tipped clusters at reef
top. At Nature’s Way, I saw more healthy
staghorn than in all the Caribbean venues
I’ve dived combined. Home to undulating
black ribbon worms, at least six species
of sweetlips that could suck a golf ball
through a garden hose and Pacific giant
clams with colorful mantles, Nature’s Way
was kaleidoscopic.
The hard coral reefs, which rise to
inches below the surface, are pristine –-
certainly the healthiest and most colorful
I’ve seen. Except for a couple that
have suffered storm damage, most sites
have magnificent stands of branching corals
from large elkhorn to tiny, delicate
blue- and pink-tipped clusters at reef
top. At Nature’s Way, I saw more healthy
staghorn than in all the Caribbean venues
I’ve dived combined. Home to undulating
black ribbon worms, at least six species
of sweetlips that could suck a golf ball
through a garden hose and Pacific giant
clams with colorful mantles, Nature’s Way
was kaleidoscopic.
The hard corals offered the perfect
  backdrop for a rainbow of slender anthias.
  Like tiaras of precious stones, they
  glittered in the strong Australian sun.
  Colorful damsels and reticulated and humbug dascyllus darted in and out of the
  protective arms of the coral as if driven by a frenzied calliope.  
Surfacing from this wonderland, I could see the solid footprint of a 72’
  steel catamaran with two aft ladders leading to a spacious dive deck. The Nimrod,
  which can adequately handle the 18-passenger max, is clean and in good repair,
  thanks to the wry, cerebral mechanic and raconteur, Mark. The generator and compressor
  are decently muffled. Between dives and meals, I repaired to my berth for
  note-taking and a nap. Like all the cabins, it had individually controlled AC,
  reading lights, dark wood veneer, and a private head and shower. The onboard
  desalinization system provided plenty of water, but it became tepid at peak usage
  so I took my shower first thing.  
The craft has two double cabins, one with a single large bed, the other with
  two single beds. The four quad cabins are considerably cozier, but the design
  gives some relief since two beds are forward of a small central area where the
  head is and two are aft. Still, if you’ve got a roomie who snores or needs Beano,
  it’s going to be a problem. The two aft quads have single berths, while the forward
  two have V-berths, and can be configured as double staterooms with full-sized
  double beds and twin upper bunks.  
Food was plentiful, if not gourmet. Colin, who was filling in for the vacationing
  chef, and Carlie, who served as steward and social director, worked hard
  to have food out before and after every dive. Though he was shorted on the boat’s
  meat order (for this we missed a half day of diving?), Colin kept the menu varied.
  Breakfast was an assortment of cereals, mixed fruit bowl, hash browns, fatty
  Aussie bacon, pork sausages, and instant eggs. Lunch could include sandwich meats
  and cheeses, pasta with various sauces/fillings, fresh green salad and ice cream.
  For dinner, it was a fresh green salad, a cooked vegetable or two, potatoes,
  chicken breast or wings, pizza, fish or red meat. There was always dessert, sometimes
  as fancy as Pavlova and plum pandowdy. The web site says that Aussie beer
  and wine are included in the price. We were initially charged and had to wrangle
  until midweek to get the Captain to concede.  
We ate in the primary common area, the salon, where we also socialized, had
  photo shows and dive briefings. A large table is in the center, with banquettes
  along both sides. It was snug and the AC was feeble, making for some sticky meals.
  The rear upper deck was outfitted with tables and chairs, as well as seats along
  the stern railing. It was a good spot to enjoy the beer, though the few smokers
  found it was an area where they would minimally offend others.
I did manage to get in 23-hour longdives,
including three night dives, in
our five plus dive days. Before each
dive, the chief divemaster, Demi, with a
conspicuous grin and profuse head bowing,
gave an amusing and adequate briefing
with basic drawings. Since many experienced
divers went their own way as soon
as they hit water, the recommendations of
no depths below 130’, starting the safety
stop when tank pressure reached 750psi
and not surfacing without a buddy largely
went in one ear and out the other. But
with their impressive diver check system,
it was unlikely we’d go missing, as did
the Lonergan couple, the thinly veiled
subjects of the movie “Open Water.” The
far north Great Barrier Reef is not
the place to get lost or left behind.
The crew logged each diver entering and
reboarding, recording depth and time. If
a diver sat out, he was required to sign
off. The DM carefully checked the list
before leaving the deck.
One Nimrod quirk is to return divers
  who surface too far from the boat by
  hauling them through the water behind the
  inflatable. I felt as if I were troll
  bait for the tiger sharks that visit this
  turtle breeding area and did not like
  being exposed to jellyfish stings.  
Tanks are filled in place and readily
  available. However, they couldn’t
  keep up with 15 divers who wanted Nitrox
  -- about half the divers had to settle
  for it every other dive. In return,
  the Explorer charged $AU75, half of the
  advertised price for unlimited Nitrox.
  There is a dedicated camera rinse tank,
  but the general rinse tank quickly got
  funky and should have been changed twice
  a day.  
At Black Rock and Raine Island, I
  got up close and personal with schools of
  massive bumphead parrotfish, some 4-ft.+.
  As they smashed chunks of reef with their
  rhinoceros-like protuberance and gnawed
  down the pieces, I pondered how many fine
  white beaches one poops out in a lifetime.
  Just one of these fellows excretes
  thousands of pounds of sand per year.  
Nearly as impressive and far more
  composed are the solitary, hulking, Maori
  wrasse. Casting a curious green eye at
  the diver as they pass, they soon disappear
  to wherever a fish of that size goes to vanish. I saw a few gray reef sharks, juvenile whitetips, and adolescent
silvertips, and tucked under spreading table coral a sizable tawny nurse shark
with perfect café au lait skin.
The terminus of our itinerary was Raine Island, a blip of sand that serves
  as the world’s busiest nesting site for Pacific green turtles. Nearly 15,000
  were once counted in a single night. It is a protected reserve accessible only to
  authorized researchers and park officials, but it can be dived within limits by
  special permit. I eagerly anticipated our first dive, so it was anxiety-producing
  when two comically officious Queensland rangers, who looked like they’d been
  sucking on lemons, boarded and secreted themselves with the Captain for nearly an
  hour. After they departed, we were told that a “new regulation” prevented us from
  diving within 3 km of the island. After the week’s earlier disappointments and
  misunderstandings, this moved our even-tempered group leader to get on the horn to
  the front office and demand action or a refund.  
So, we dived Ruined Reef. As a “consolation” site, it was pretty darn nice.
  Bluespine, spotted and white margin unicornfish paraded about like prevaricating
  Pinocchios, while blackbelt and blackfin hogfish bedeviled bottom prey. The usual
  low profilers, such as tailspot squirrelfish and ringtailed cardinalfish, demurely
  observed from their hiding places.  
Early next morning I rose to watch
  the nesting turtles drag their bulk back to
  the sea. Through binoculars the sandy beach
  looked as though it had been subjected to
  a crazed dune buggy race with uncountable
  tracks running up and down. The sea was so
  littered with green turtles that wherever I
  looked with my binoculars an animal or two
  popped up for air. And then, to everyone’s
  great relief, the rangers returned, hats
  in hand, and offered a sincere apology for
  their misinterpretation of the regulations.
 I went scouting the turtles with
  gusto. They were rather skittish, so slow,
  nonthreatening approaches from above and
  behind worked best to get extended periods
  of viewing. Finning past these handsome
  creatures with carapaces of vibrant green
  and gray tones, I had happily achieved my
  goal.  
Given the grueling haul from Los
  Angeles to Portland Roads, for a single week
  this trip alone isn’t worth the hassle. But,
  with an additional week diving at another
  venue –- or a week enjoying the splendors
  of Australia, it becomes worth the investment.
  But I’d first research the Undersea
  Explorer, which also makes the run, and if I
  were to choose the Nimrod, I’d get a written
  guarantee from headquarters that the boat
  would be provisioned for an on-time departure
  or money back. Otherwise, 20 hour in
  transit and a $2900 liveaboard trip is just
  too much.  
- Doc Vikingo
 Diver’s Compass: Upon arrival, the captain told us we would be
required to pay a $60 fuel surcharge . . . The Nimrod Explorer
is owned by an American company, Explorer Adventurers, which runs
live-aboard in the Caribbean . . . I paid $2,900 for my share of
a double cabin, (and quad was $2145) which included alcoholic beverages
and any needed rental gear. Other seven-day trips start
at $2145 (but only $1345 if you bunk in a quad) . . . For Nimrod
details and pricing see www.explorerventures.com . . . This itinerary
is only done twice a year, in our late autumn, but there
are several other excellent Coral Sea trips, where the diving surpasses the Great
Barrier Reef . . . Nimrod has a first aid kit and 02, radio, automatically deploying
inflatable life raft, life vests, fire suppression systems, emergency lighting
and EPIRB (boat only, not divers). Nearest hyperbaric facility is in Townsville, a
couple of hundred miles south of Cairns . . . For overnights in Cairns, go to www.needitnow.com.au for the best deals. I stayed at the Coral Tree Inn (www.coraltreeinn.com.au), a good value.
Diver’s Compass: Upon arrival, the captain told us we would be
required to pay a $60 fuel surcharge . . . The Nimrod Explorer
is owned by an American company, Explorer Adventurers, which runs
live-aboard in the Caribbean . . . I paid $2,900 for my share of
a double cabin, (and quad was $2145) which included alcoholic beverages
and any needed rental gear. Other seven-day trips start
at $2145 (but only $1345 if you bunk in a quad) . . . For Nimrod
details and pricing see www.explorerventures.com . . . This itinerary
is only done twice a year, in our late autumn, but there
are several other excellent Coral Sea trips, where the diving surpasses the Great
Barrier Reef . . . Nimrod has a first aid kit and 02, radio, automatically deploying
inflatable life raft, life vests, fire suppression systems, emergency lighting
and EPIRB (boat only, not divers). Nearest hyperbaric facility is in Townsville, a
couple of hundred miles south of Cairns . . . For overnights in Cairns, go to www.needitnow.com.au for the best deals. I stayed at the Coral Tree Inn (www.coraltreeinn.com.au), a good value.