NZ SEALION TRUST NEWSLETTER

Our Mission: to promote the protection and conservation of the threatened New Zealand sea lion and related species through research and public education

http://www.sealiontrust.org.nz

NEWSLETTER AUGUST 2010

Topics in this newsletter

1) New Threat Status for Sea Lions
2) Amelie’s research
3) Pup update

New Zealand Sea Lion Trust
Chairman- Shaun McConkey
Treasurer- Brian Templeton
Trustee- Steve Broni
Trustee- Colin Emslie
Trustee- Neville Peat

New Threat Status for Sea Lions

New Zealand sea lions have just been re-listed as “Nationally critical” following a recent review of marine mammal threat listings in New Zealand. What does this mean? There are several reasons for a species to be listed as nationally critical. For the New Zealand sea lion there are two key factors:
1) the population is estimated to be less than 3000 mature individuals;
2) the population has declined by almost 50% in the last 10 years which can be extrapolated to more than 70% over a period of three generations.
Go to the following link on the DoC website for further details on the threat classification system
(http://www.doc.govt.nz/publications/conservation/new-zealand-threat-classification-system-manual/)
This puts New Zealand sea lions under the same threat status as Kakapo.
What will it mean for their management? Likely nothing! DoC, Otago Conservancy, are working their way through the species management plan which is the only legislative guidelines that DoC has. The Population Management Plan has been put on indefinite hold due to apparent problems with the process of creating and implementing these plans. The current government is likely to have little enthusiasm for resolving this issue.. And the fishing industry will continue to stall and confound any attempt to change the status quo.

So what needs to happen?

1) We need to let the government know we are not happy to let a nationally critical endemic species slip closer to extinction for the sake of a short-term unsustainable economic gain. The power of public opinion was obvious in the recent mining of national parks debate.

2) We need to get more accurate information on the causes of the sea lion population decline. It is clear that sea lions are being caught in fishing nets, and not just the squid fishery (we need 100% observer coverage now to get reliable bycatch rates in the Scampi and Southern Blue Whiting fisheries). Hoki are an important part of sea lion winter diet; with the collapse of the Hoki fishery recently there is evidence sea lions may be working to their physiological limits when feeding. Some scientists believe that the carrying capacity of the subantarctic region has been reduced as it appears other species are also struggling.

3) We need to know EXACTLY how many sea lions are being caught. By-catch rates are currently using historical data (suspect to begin with) that does not take into account changes in fishing practices such as longer duration fishing tows.

4) We need to know what effect sea lion exclusion devices (SLEDs) are having. Are they effective in releasing sealions from nets. How many are injured? How many survive? Despite having SLEDs attached for 10 years now, we still don’t know this.

5) The onus should be on the fishing industry (as the ones making money from the fishery) to show they are NOT having a negative effect on the marine environment instead of the New Zealand Public having to show that they are.

6) The government needs to realize with this population decline that the current management techniques are not working and something needs to change. Why does the population model used by the Ministry of Fisheries to set the bycatch limit not predict the decline we are observing?

7) We believe the most practical approach is to reduce the sea lion bycatch, by increments, each year and this will give the fishing industry time to develop techniques and collect ‘accurate’ data to show the true extent of the impact on the sea lion population.

What can you do?

Write to the Minister of Fisheries, Phil Heatley (see our website for details), and ask him to reduce the bycatch, collect reliable data so informed decisions can be made, and change the burden of proof to the fishing industry not the people of New Zealand who value this icon of our natural heritage

2. A Research update from Amelie Auge

Last autumn during April and May, eight female New Zealand sea lions were satellite tracked at the Otago Peninsula for the third and last year of my PhD. In the two previous years, we had studied the foraging (feeding) behaviour of all known females from the Otago Peninsula. In 2010, we added Cockle and Lena to this list (born in 2008) and this means we now have data for all the females 2 years and over as in 2010. Both of these young girls (including Lena that Honey was still nursing!!) dived down to 120m and went as far as 17km offshore so this means they are developing well and exploring new areas, which is great news. Lena and Honey were together most of the time onshore, and to a lesser extent at sea. Also, this year, the aim was mainly to determine if the female sea lions use the same areas to feed each year. And, indeed it appears they do, as you can see on the map that presents the marine areas used by Honey in 2008 and in 2010.

In total, six females were satellite tracked during two different years. They all showed high levels of site fidelity to feeding areas and their diving behaviour was also similar with a mean depth of approximately 35m. Gem continued to have the deepest dive record (this time it increased to 418m) but she did this only once in two months (the rest of the time she ived within 30m of water!). So once again, it was a very successful year.

Now, you’ll have to excuse me but I have to get back to my computer to finish analysing all that data and work on the writing, not as exciting as fieldwork but necessary both for my thesis and the sea lions ☺ Dr Louise Chilvers, my supervisor from DoC, and I, thank everyone who helped in the field and/or passed on female and pup sea lions’ sightings over the last three years. Such a project takes many people to conduct successfully and we greatly appreciated the help and enthusiasm of Trust members.
Amelie Auge.

3 Update on the 2009/ 2010 pups

In early August, we had a very successful day on the Peninsula making our monthly check on the Otago sea lions. Firstly, we spotted Patti (Katya’s 2009 female pup, tag 9001), hanging around one of her usual haunts and looking right at home ☺

We then discovered Mana (Nerissa’s 2009 female pup, tag 9002) looking slightly smaller than Patti but still in good condition. However, if recent reports of her swimming as far north as Oamaru are true, then no wonder she’s shed a few kilos!

Our best sighting of the day had to be when we came across Zoe’s female pup from this year, Becky (tag 9009;). We haven’t seen her since March and it was fantastic to see her still alive and looking so healthy and full of beans. In the same area we also came across Sandy (Nerissa’s 2010 female pup, tag 9008; see right) who looked equally well fed.

Later in the afternoon, we saw Arnie (Teyah’s 2009 male pup, tag 9003) whose size is living up to his name; he seems to love the Peninsula as we regularly see him pestering the young females, especially Cockle and Lena. Finally, we finished our day off with a lovely sighting of a healthy looking Pippa (Teyah’s 2010 female pup, tag 9006) and also of Huru (Katya’s 2010 female pup, tag 9007) who we haven’t seen for a couple of months. Huru had recently been playing in the water and only her top half was drying so she was sporting a very fetching Mohican hair do! Just as the light was beginning to fade, we completed the set of 2009/2010 pups by spotting Ethan (Zoe’s 2009 male pup, tag 9004) nervously approaching a big adult male. Lovely to see them all doing so well!!

Thanks again for all your support. Please let us know if there is anything else you would like to see in our newsletters.