For those of you that have been following my posts on the Mako shark fishing ban you may want to take a look at the following link. I’d also recommend that you download the fact sheet about the three species listed as migratory species under the Environment Protection and Biodiversity Conservation Act 1999.
Today we’ll take a look at the life cycle of the Mako shark. The marvelous mako has been clocked at around 50 kilometers per hour and is clearly the fastest swimmer of all sharks. As a matter of interest in one of my old posts I discussed the life cycle of the fastest fish in the sea – the sailfish – which has been clocked at speeds of 110 kilometers per hour. In comparison a goldfish in peak physical condition can reach speeds of just over 2 kilometers per hour! But I digress…
The mako is an ovoviviparous shark. What the?
This means that the mako gives birth to live young after their eggs have hatched and developed in the womb. A healthy mako mother’s pregnancy will last between 14 and 18 months after which time they will set off for shallow water to give birth to between 4 to 18 young sharks. A baby mako is around 75cm when born and will already have a full set of razor sharp teeth! It must take a bit out of the poor female mako as she is said to take a break from reproduction for at least 18 months after giving birth. The length of time taken to reproduce and the long break afterwards means that the breeding capacity and potential of the species is quite low. On the upside because the young are quite large they are rarely preyed upon and have good potential to fully develop. In the ocean it pays to be on the top of the food chain!
Makos are internally fertilized by males who inseminate the female with claspers that develop on their pelvic fins.
The maximum age of a mako is said to be just under 30 years. Adult females are larger than their male counterparts and can grow to 4 meters in length and weigh up to 500kg. By the way, the porbeagle shark that is also caught up in the fishing ban is thought to live up to 65 years.
Male makos reach sexual maturity at 2m in length whilst females do so at around 3m.
Although listed as a migratory species over 11500 makos have been tagged in Australian waters and it is said to be a rarity to recapture them beyond our limits. A satellite tagging program that has been going for two years in South Australia suggests that there is little predictability or set pattern in mako migration.
Interestingly this appears to be contrary to makos in northern hemisphere waters who are said to be “highly migratory” and often travel “over entire ocean basins”.
Anyway, so there you have it. In summary with such lengthy gestation periods with few pups born there is a case to be had that overfishing would put pressure on the continued existence of the mako shark. The thing is this – populations within Australian territorial waters are not over-stressed by recreational fishermen. In fact it is the recreational fishermen that continue to tag and release these species. The more data we can capture about the habits of the mako shark will serve to protect the species for years to come.
Shortfin Mako Shark - not so prevalent in the Mediterranean and East Atlantic Oceans
Greetings all,
I recently wrote a blog about the environment minister Mr Peter Garrett proposing changes to the current legislation that has impacted recreational fishing for longfin mako, shortfin mako and porbeagle sharks. See;
To recap, Australia is a signatory to an international treaty and “is prohibited to “kill, injure or take” members of a listed migratory species in Commonwealth waters”. The above sharks are in sharp decline in the Mediterranean Sea and the Eastern Atlantic ocean and have had bans placed on their capture and therefore we have been impacted as well. Trouble is they are not endangered locally and the Australian populations have nothing to do with Northern Hemisphere stocks.
So what is the current situation?
I contacted both NSW state and federal departments to check the current impact on recreational fisherman.
Here’s the drum…
1. There is a current ban in place on fishing for these species however you need to take into account the following points below
2. From an enforcement point of view there is no impact on catch and release fishing in state waters (usually three nautical miles off the coast)
3. In the Commonwealth zone (3-200 nautical miles off the coast) there will be no enforcement unless there is a significant impact on the species (ie a recreational fisherman is unlikely to make a “significant impact” and therefore can still target makos)
4. An amendment is being worked on now to take into account suitable exemptions
5. Parliament will sit on 22nd February and the amendments making fishing for the species in question legal will be introduced and hopefully approved.
Of course Mr Garrett is under fire at present due to the deaths of people involved in the insulation installation debacle. Let’s hope he keeps to the 22nd February deadline to clear the current mixed messages on the mako fishing ban.
Anyway, for now it seems like it is business as usual for mako fisherman around the country which is good news. Remember to fish responsibly and where possible tag and release and we will still be fishing for these great creatures for many years to come.
I’m very pleased with the fact that I can help people prepare to fish the area responsibly and I have had several emailers wanting to know whether or not the book will be available in published format at local fishing stores and tackle shops.
This was always the plan in the beginning and my publisher was ready to push the button and along came the global financial crises and that put an end to that. As you can imagine Weipa is a small town and as such only a small run of 2000 copies was planned for production. The idea behind the book was to be able to give advice to people BEFORE they made the trip up north and so I’ve bitten the bullet and made it available in eBook format so that there are no further delays in getting it into the hands of people that actually need it today. Unfortunately it won’t be available from fishing stores and tackle shops in the near future.
With the wet season nearly over, it’s coming up to prime fishing time in Weipa and the eBook will help you make the most of your trip.
Even if you’re not heading off to Weipa you may like to take a look at it anyway – the chapter on “The Seven Habits of Highly Effective Fish” is worth a read on its own!
More than just an eBook, it’s over 40,000 words of information jam packed into one easy to read PDF file!
The reason I put this book together was because the Fishing & Reef Tour Specialists fished this magnificent paradise a few years back and when we were preparing to go we just couldn’t find any information about the place. Being a remote fishing destination we wanted to be prepared as much as possible. If only I had this eBook BEFORE we left!
I wanted to make sure that no one else would have to do as much research as we did so that when they got to Weipa they knew exactly what to do and where to go to get straight into the fishing action.
Yes, the book does give you directions to fishing hot spots, what to take including which lures (and for that matter it also gives you the low-down on when, where and how to catch mud crabs in Weipa) but it also provides insightful information about responsible fishing.
Anyway, more detailed information is available at;
Shortfin Mako Shark - not so prevalent in the Mediterranean and East Atlantic Oceans
Greetings all,
Whilst the Environment Minister Mr Peter Garrett is not handing out free roof insulation he is on to more pressing issues – like redrafting legislation that would have seen the end of recreational mako shark fishing throughout the country at the end of January. Angry anglers from around the nation put together a petition signed by over 5000 people seeking to have the proposed ban lifted. Thankfully common sense – an often missing element in Australian politics – seems to have won through and legislation will be introduced to see keen Australian fisherman legally still chasing the marvelous Mako shark after January 31st 2010.
For the record the longfin mako, shortfin mako and porbeagle sharks were to be included on the endangered species list and fishing banned for these species as from January 29, 2010. Many boaties have invested plenty in fishing tackle and vessels to be able to catch these species and of course charter boat operators were concerned for their livelihoods. Others contemplated the ban spreading to other recreational targeted fish such as coral trout and giant trevally to name a couple and tackle stores around the country were left very concerned indeed.
That being said – why is the mako shark being added to this list?
Well apparently the mako’s problem is not associated with Australian waters but their numbers have dwindled in the Mediterranean Sea and the Eastern Atlantic Ocean. The United Nations sponsored Convention on Migratory Species is listing several sharks, including short-finned makos, for complete protection and Australia is a signatory to an international treaty and “is prohibited to “kill, injure or take” members of a listed migratory species in Commonwealth waters.”
The funny thing is the local population of mako’s have nothing to do with northern waters. Biologically the ban makes no sense whatsoever because there is no sharing of populations between the impacted areas. Furthermore, the mako’s are not under threat in Australian waters at all and are a popular tag and release species. In fact, the Fishing and Reef Tour Specialists are off to the southern coast of NSW to target this species in an overnight adventure in June of this year which could have been called off if this nonsensical ban continued.
Bans are already in place for other sharks such as the great white and the grey nurse.
Next week I will run through the life cycle of the mako shark.
Sea you later,
Skipper Meggs
PS. For the latest update on the mako fishing ban see;
Posted by Meggs | Survivor Samoa | Posted on January 22nd, 2010
Greetings,
It’s been a long and interesting season of Survivor Samoa with probably one of the most scheming players of all time. I thought you’d be interested on how the cheque presentation went the morning after the reunion episode so I’ve included the video below. Please accept my apologies for the CBS adverts before the main video starts – that’s the way they make ‘em!
Anyway have a watch and see if you concur with my thoughts about building a bridge and getting over it…!
Just for the record I’ve also included an exclusive interview with the now infamous Russell Hanzt.
Posted by Meggs | Survivor Samoa | Posted on January 22nd, 2010
Greetings,
Well it’s sad news for those of you that remember the 2005 Survivor Palau series which was made famous by Johnny Fairplay’s antics and in which Jennifer Lyons managed fourth place.
Unfortunately the Survivor star has finally succumbed to breast cancer having been diagnosed shortly after her appearance in the show.
Posted by Meggs | Survivor Samoa | Posted on January 19th, 2010
Greetings all,
Ok, well it’s been one hell of an interesting season this year in Survivor Samoa and for those if you watching events unfold in Australia but who aren’t able to watch the series on TV at the time Channel Nine have scheduled it for in last week’s post I included series 9 through to 14.
Today for your internet viewing pleasure uninterrupted by annoying commercials I invite you to watch the season finale. I must admit I am sold on watching TV series in this manner and I’d even go so far as to watch them on the Channel 9 website if only they would load them!
Anyway, it’s the same deal as last week. The final episode comes in 8 parts 15.1, 15.2, 15.3, 15.4, 15.5, 15.6, 15.7, 15.8 whilst the reunion comes in 4 parts R.1, R.2, R.3, R.4. You’ll see these references appear on the screen after viewing the previous sections. If you have any trouble just let me know through the comments section and I’ll help out.
Posted by Meggs | Survivor Samoa | Posted on January 9th, 2010
Greetings all,
Ok, I have a confession to make – I like to watch certain reality TV shows and the Survivor series is one of them.
Last week I was out with friends and missed a double episode just as I thought it was getting interesting and towards the end. For those of you that follow the show I was keen to see how far the evil Russell would get but I missed the show entirely. So I did what anyone would do nowadays and checked out the Channel 9 website to see if I could view it there.
Typical, they don’t have any episodes that you can stream from their website. What’s more is that their website had a lot of upset fans complaining about the fact that any episode they missed, they weren’t able to access through Channel 9.
Anyway, as a public service I’ve included the beginning of episode 9 through to 14 below and there are four takes in each episode (eg 9.1, 9.2, 9.3, 9.4. 10.1, 10.2, 10.3, 10.4 etc) you will see them appear once you have finished watching the first 10 or 11 minute video below. I’ve managed to watch the entire series through to the end online – even the reunion! Enjoy and let me know if there are any technical issues.
For those of you that are interested I will include the final episode and the reunion in next week’s blog.
A double bunger of blue swimmers with some already in the holding pen
Greetings!
A week or so ago one of the Fishing & Reef Tour Specialist’s crew, Morro and I took a well deserved break on Botany Bay. The fishing was tough and the Bay looked like a mess with the Desalination Plant being built. It’s hard to say whether this is a contributing factor to Botany Bay’s fish drought but on the surface of the water it truly looks like an environmental disaster with sections of the Bay kept boat free with weird looking floating objects snaking their way from one side to the other. Progress? I’m not so sure…
Anyway all was not lost as before we went fishing we threw out ten witches hats to try and jag some Blue Swimmer crabs. With Xmas coming on it seemed very appropriate. In NSW there is a limit of five witches hats per person so we were at our limit. At the end of the day we lifted the traps and were rewarded with 6 reasonable size crabs. Success! These were all headed for the freezer and then the pot.
But what is the story behind the Blue Swimmer crab?????
Well the Blue Swimmer crab (or Portunus Pelagicus) is part of the Portunidae family which also includes those sensational eating mud crabs that I’m yet to set a trap for this summer in the Georges River. The widest part of the crab, the carapace or shell, can grow up to 21cm and their claws can have a span of up to 80cm. They can weigh up to a kilogram. As their name suggests they are very good swimmers and their last two “legs” act as paddles. The paddles also have a tendency to snag the netting of a good witches hat! Males have a narrow pointed tail flap on the underside of their shell whereas a female has a wider, more rounded flap. Males also have blue elongated pincers whilst females have shorter grey/brown pincers.
In the autumn months the male crab begins to court the female for four to ten days by carrying her beneath him and fighting any other crab that comes near. Apparently the male assists the female in moulting her shell and turns her over to mate when she is still soft shelled. Afterwards he still protects the female for another three or four days to allow her shell to harden before dumping her and chasing other female crabs. Interestingly the female retains the sperm until the following summer when her ovaries are fully developed. This could also explain why most fisheries compel fisherman to release all female crabs regardless whether they appear to be carrying eggs or not.
A female blue swimmer crab will produce between 180,000 and two million eggs (I still don’t know who counts these things!) and carry them on her abdomen. Such a crab is said to be “berried”. The eggs will change from orange to black and will be incubated for about 18 days. The female will shake away the mature eggs which hatch into what is known as “zoea”. These float in the tide for four to six weeks and can be swept up to 80km out to sea. Most fall prey to other marine creatures but a small percentage make it to shallow nursery areas where they grow and moult numerous times before becoming the size of a 10c coin and taking on the shape of a crab. At this stage they are known as Megalopae and each time they moult they can increase their size by 20% and their weight by as much as 80%.
By autumn they are between 3 to 6cm in width and by winter they are at least 9cm wide. The winter months slows down their growth and before their last moult the females will mate with a male for the first time and start the whole cycle off again.
I am always amazed at the amount of male blue swimmers that are caught as opposed to females. I estimate that it’s probably in the ratio of 10 males to one female. This may be because the females are “busy” with their male partners whilst the males are more likely to be out foraging for food. If you have some theories on this I’d be happy for you to make a comment below.
