There have been many encounters with unknown creatures off the coast of New Zealand, with the East coast being particularly favoured.
There is a very good reason for this, running parallel to New Zealand's coastline is the Hikurangi Trench. A deep gouge on the ocean floor, that descends in places to depths of 3,750 metres (12,300 ft).[
(Lewis, Collott, & Lallemand, 1998, pp. 441-468.)
New Zealands unique oceanography
These deep troughs bring a wealth of nutrient rich organisms to the surface allowing for a mass of biodiversity to flourish in the nutrient rich upper waters.
Krill are profuse here along with smaller fish species which create a nutrient rich environment for larger predatory animals such as Giant Squid, which in turn are preyed upon by Sperm Whales. So there is no deficit of vast food supplies for large predatory animals cruising the depths of New Zealand's coastline.
Where the Hikurangi Trench joins up with the Tonga Trench, the area is heavily spotted with areas of geothermal activity which provide warm waters as well as a warm current which flows from the equatorial region.
This area of the Tonga Trench has a rich diversity of marine life previously undiscovered until recent expeditions. This is a very harsh environment where reshaping of the seafloor is happening continually, to quote from the results of a joint project between the Universities of Durham and Oxford, and funded by the National Research Centre.
"Where the Pacific plate collides with the Indo-Australian plate, it is forced downwards into the trench, a subduction zone, and the volcanoes are carried with it.
The trench, reaching a depth of 10.9km, forms the second deepest stretch of seabed anywhere in the world - easily large enough to hold Mount Everest"
What would make this an ideal nursery and breeding place?
The abundant food supply, warm, water and lack of large predatory animals would make this an ideal breeding and nursery ground for Mosasaurs. Migrating whales along these routes would also provide a range of suitably sized animals for the young mosasaurs to feed on, and just returning from the feeding grounds would make these whales wholesome additions to their diet.
Personally, I think the primary reason that many of these creatures are avoiding detection is the fact that they have learned to avoid the sound of a ship's engine and stay well away from any encroaching vessel or main shipping lane.
These out of the way areas often lead to shallow bays which are warmed by the circum-tasmanian current which brings warm water to the Bay of Plenty, which coincidently boarders the Kermedec trench. Warm water, shallow bays and a deep nutrient rich feeding ground create ideal nutrient rich conditions. Likewise a high percentage of creature observations have been made in these very waters.
So what has been seen in these waters?
The earliest known reference to Mosasaur like creatures in New Zealand waters comes from a report dated August 1st
1899 from the Union Steam Ships Chief Officer of the Rotomahama, Lindsay Kerr.
He reported a huge Conger Eel, except it had two fins, one on each side of the body. This colossus Rose up to a high of 30 feet out of the water. This sighting occurred near the Portland Light situated between Gisborne and Napier.
Right in the area of suitable Mosasaur habitat coincidently.
When shown pictures of various types of Eels, Mr Kerr said it had a more crocodilian type head rather than anything he was shown.
In April 1971 the crew of the Kompira Maru
saw a "Bug-Eyed Monster" which resembled a large crocodile, but had fins instead of Legs, which were clearly visible as it leaped and dived under the water.
1972 three women were whitebaiting at the mouth of the Orari River near Temuka watched a huge creature wallowing in the breakers about 30 m away from them.
They described a light grey lizard like beast that was around 15 m long, which at one point opened its mouth to reveal numerous small sharp teeth.
There is nothing to be said to make me think otherwise but personally, I do believe these creatures are out there as there have been too many sightings that are so closely reminiscent of mosasaurs as to be easily dismissed.
There have been 11 reported sightings of Mosasaur like animals reported in New Zealand waters, a higher number than anywhere else.
Are they a new species?
I would more like to think of a Coelacanth scenario, an ancient species that has adapted to survive into the modern age.
We are still but children taking our first unsteady paddling steps into a very wide and portentous ocean that holds many secrets and undisclosed treasures we thought once lost.