Fur Seals: Habitat Preferences and Human Interaction

Fur seals: habitat preferences and human interaction

1.  Project title

Fur seals: habitat preferences and human interaction

2. Proponent(s) details

(a)  Chief Investigators

1 / 2
Title / Professor / Mr
Name / Robert Harcourt / Matt Carr
Institutional Affiliation / Macquarie University / Jervis Bay Marine Park
Address / North Ryde, NSW / PO Box 89, Huskisson, NSW, 2540
Phone Number / 02 9850 7970 / (02) 4428 3001
Fax Number / 02 9850 7972 / (02) 4441 7756
Email / /

(b)  Co-investigators

1
Title / Dr
Name: / Justin Clarke
Institutional Affiliation: / Shoalhaven Veterinary Clinic
Address: / 109 Berry St, Nowra, NSW, 2541
Phone Number: / (02) 4421 3150
Fax Number: / (02) 4423 0343
Email: /

(c)  Primary Contact for Project

Name: / Matt Carr

3. Public project summary

Australian and New Zealand fur seals are currently recovering from historic over-exploitation and are expanding their ranges within Australian waters. Both seals are colonising habitats along the NSW coast, where they will compete for resources with each other and with human use. Understanding habitat preferences of these seals at a time when their populations are low, will greatly enhance the success of future conservation and management strategies both in NSW and elsewhere where seal populations are expanding. This project will examine haul-out and foraging activities of these seals.

4. Research priority areas

Interactions between fur seals and humans often leads to disturbance or harm to the animals and disruption to human activities. Two species of fur seal reside in Australia: Australian fur seals Arctocephalus pusillus doriferus and New Zealand fur seals Arctocephalus forsteri. Both are native to southern-Australian waters and were harvested almost to extinction in the 19th and early 20th centuries. After remaining at low numbers for over 100 years, populations’ recoveries were first recognised during the late 20th century. Each species now has a population in Australian waters of over 100,000 individuals. As the populations recover, both species are expanding their ranges, and the number of seals that haul-out at locations along the NSW coast has increased significantly in the past 30 years.

The degree of occupation of NSW coastal water by fur seals prior to sealing is not known. Up until about the 1960’s, however, fur seals hauled out at Seal Rocks on the mid-north coast demonstrating that habitat was available to them prior to the current colonisation. While fur seals have been virtually absent from the NSW coast, human activities have increased significantly. NSW is now the highest populated area of Australia (>5 million people). Accordingly, there is significant coastal development and human use of marine resources and a network of marine parks have been established in NSW to protect representative marine habitats and biological diversity and maintain ecosystem processes. The extent of interaction with human activity is currently unknown as fur seals recolonise the NSW coast.
This project will focus on fur seals that occupy haul-out sites in the south coast region of NSW, principally around Jervis Bay. There, both species occupy a range of sites within and outside Jervis Bay Marine Park and Batemans Marine Park. Previous studies have demonstrated that these sites not only contain seals year-round, but also represent important resting site for fur seals that travel up and down the NSW coast.

Human interactions are increasingly common as the northward range of fur seals recovers to its pres-sealing extent. The prevalence (or absence) of human interaction and harm is coincident with marine park protection and other spatial management of human activities eg. ease of public access to locations and spatial fisheries management. Spatial management such as marine parks can address the issue of disturbance and harm caused to fur seals. For this management to be successful, it must be informed by accurate data on both haul-out behaviour and at-sea movements. Most of the available science focuses on where females forage at breeding colonies, which are predominantly in the Bass Strait and South Australia. Haul-out behaviour and foraging preferences at the northern end of the fur seal range are poorly understood, and this has implications for the management and recovery of these species as they recolonise their pre-sealing range.

At-sea interactions are predominantly with fishers. Spatial zoning of marine parks (which determines where fishing can occur) can limit these interactions if correctly planned. Beyond mariner park boundaries, spatial fisheries management also plays a role. Interactions at haul-out locations can also be limited by spatial zoning of marine parks by focussing land-based access such as rock fishing into areas where it will cause least disturbance to seals and facilitate their ongoing recovery.

By tracking fur seals fitted with GPS and time-depth-recorders (TDR), we are able to gather information about fine-scale foraging and haul-out behaviour. With this information about habitat preferences we will be able to evaluate the relative importance of different habitats. When overlaid with information about habitat types, spatial zoning and distribution of human uses we will be able to quantify the extent and potential for interactions and adjust spatial management accordingly, to minimise the potential for disturbance and harm to seals caused by human uses.

Tracking seals once they leave the haul-out sites surrounding the NSW coast and return to breeding colonies will also provide valuable information on the population structure beyond NSW, and where the apparent increase in the NSW population is being seeded from. This has important implications for conserving the population as a whole rather than just protecting the animals while they are resident in a marine park.

5. Policy

Both Australian fur seals and New Zealand fur seals are listed as Vulnerable species in NSW under the Threatened Species Conservation Act 1995.

The Australian Government Action Plan for Australian Seals (Shaughnessy, 1999) includes the following stated research objectives:

- “Investigate feeding ecology and foraging behaviour”

- “Obtain information on movements and feeding areas using satellite-linked radio transmitters and time-depth recorders”.

The Action plan identifies both species as Lower Risk, Conservation Dependent in Australia.

Jervis Bay Marine Park Zoning Plan (and zoning plans for other marine parks, including Batemans Marine Park where tagged seals from the pilot study have visited) is established to conserve marine biological diversity and marine habitats by declaring and providing for the management of a comprehensive system of marine parks andto maintain ecological processes in marine parks, of which seals are an important part. Accurate spatial information about fur seals use of habitats within the marine park is necessary in order to inform marine park management.

Fisheries Management Strategies – various fisheries in NSW with seal interactions, including Ocean Trap and Line Fishery and Ocean Trawl Fishery which operate in the research area.

6. Project objectives

The project has a number of objectives:

1.  to apply GPS tracking devices to seals at haul-out locations in the Jervis Bay region and track the seals for following weeks

2.  Elucidate behaviour, haul-out usage and foraging habitats of fur seals along the NSW coast

3.  Improve understanding of the processes of colonisation of the NSW coast by fur seals

4.  Compare and contrast overlaps of habitat usage and marine park zoning

5.  Compare and contrast overlaps between habitat usage and human use eg. fisheries

6.  Improve knowledge and public awareness of fur seals along the NSW coast, their distribution and role in local marine ecosystems

The project was run as a pilot study in Jervis Bay Marine Park in 2011 and 2012, to assess the effectiveness of the methodology and to determine how useful the results would be to applied management of fur seals. Four tags were deployed to inform the following research questions:
- Do individual animals show fidelity to a particular haul-out site or is there connectivity between haul-out sites within the marine park and outside?

- How long are individuals spending within each of the spatial management zones within the marine park and outside the marine park?

- Of the time spent within each spatial management zone, what proportion is spent hauled out or foraging, where interactions with human uses are most likely?

The pilot study showed that the method used for capturing and deploying the tags is viable. The preliminary results have indicated that the data gathered can be used to answer the research questions posed above. It is therefore our intention to continue the project with a greater number of animals so that the results can be used to inform future management of marine parks in which seals are present, and more broadly, to inform conservation of fur seal species as they re-colonise previously inhabited areas, to minimise disturbance and possible harm as a result of human interactions that can be addressed through spatial management.

7. Project methodology

Fur seals will be captured and chemically restrained using Zoletil to avoid unnecessary stress and risk to the animals. A detailed outline of the capture and restraint methodology is at Appendix A. A Wildlife Computers GPS tag will be adhered to the animal behind the scapulae using a 2 part adhesive. The tag will separate from the animal during the moult if the animal is not recaptured and the tag removed beforehand.

Where possible, animals will be recaptured using the same methodology and the device will be retrieved, data downloaded and the device redeployed. Data is still received from animals that are not recaptured. The data are transmitted via satellite and can be used to inform questions about the animals’ movements, haul-out behaviour and foraging depth. It is desirable to recapture and recover the devices where possible as higher resolution spatial and foraging data are available if downloaded directly from the device. These higher resolution data can be used to inform exactly which habitats the seals are foraging on and how those habitats are being utilised for foraging eg. benthic, mid-water etc. This information can be used to determine which areas within the marine park (and outside) are most critical and deserving of protection, and where harmful interactions are most likely and need to be more intensively managed.

Wildlife Computers GPS tags will be used because they offer GPS, satellite transmitting and time-depth recording functions required to obtain the necessary data. Standard geolocating tags will not provide the resolution required at such a small spatial scale.

Tags will be deployed from May – October each season, when the seal population is at its peak and there is a higher likelihood of the seal returning to an area where the tag can be recovered. From October onwards seals begin returning to breeding colonies in the Bass Strait.

A Geographic Information System (GIS) will be used to quantify the success of existing marine park spatial management in minimising potentially harmful interactions and to identify areas of importance for at-sea movements and haul-outs. This information can be applied directly to future marine park management to improve spatial zoning to better complement the habitat needs of fur seals.

8. Data collection

The above methodology has been successfully used to deploy tags on 6 fur seals during the pilot study, and in other research projects studying a range of seal species. Approximately twelve additional tags will be deployed in 2013.

Data retrieved from recovered tags are downloaded manually be connecting the tag directly to a computer and accessed via the Wildlife Computers DAP software.

Data from tags that are not retrieved are recovered via satellite download from the ARGOS system of satellites.

Based on the current pilot study and the experience of researchers using the same methodology, tags will transmit for ~90 – 200 days before their battery expires or the tag falls of the animal.

9. Location/s of data collection

Fur seals will be tagged opportunistically at haul-outs between Five Islands Nature Reserve and Montague Island. The area of focus for capturing and tagging seals will be the haul-out sites within Jervis Bay Marine Park. In particular, Lamond Head provides easy and safe access and is a workable area where recovery of the devices was achievable during the pilot study. Based on anecdotal evidence and the results of the pilot study conducted in 2011/12, Lamond Head appears to be a staging point for seals travelling both north and south, with seals returning to this site after hauling out elsewhere periodically.

10. Data analysis

Initial analysis of spatial and diving data will be made using the proprietary Wildlife Computers DAP Processor software. Spatial and foraging data will then be overlaid with detailed marine park zoning data, habitat spatial data and fisheries data using ArcView GIS to determine the likelihood of harmful interactions with human use.

The likelihood of disturbance in each of the mapped locations will be inferred by quantifying the percentage of at-sea and haul-out time in locations with different levels of exposure to disturbance eg. sanctuary zones vs heavily fished locations, ease of access, proximity to human settlement etc.

11. Project outputs

Expected outputs / Date of completion (mm/yy)
Tagging completed / 10/13
Public presentations / 1/14 and ongoing
Report to AMMC / 3/14
Manuscripts and reports to managing agencies / 4/14 and ongoing
Improved understanding of spatial conservation needs for re-establishment of pre-harvesting range / 4/14 and ongoing

12. Technical and management capability

Prof Rob Harcourt

Prof Harcourt has over 25 years experience with marine mammal research including fur seals, dolphins and southern right whales. He has been the CI for a number of collaborative investigations over the last 20 years with international partners from Scotland ; NZ; USA ; South Africa and France. The total budget for these various research projects is just over seven million dollars. He has been Head of Department and Director of Marine Science at Macquarie University since 2001 managing a department of 18 staff and annual budgets comfortably exceeding one million dollars

Mr Matt Carr is the Manager of Jervis Bay Marine Park. Matt has 12 years of experience in marine park planning, development and operations management including review and amendment to marine park spatial management to align with contemporary research outcomes. He has worked in marine parks in NSW, the Great Barrier Reef and Commonwealth jurisdictions. Matt has extensive experience in research field work, including the capture and tracking of fur seals, sharks and fish and in the management and handling of marine wildlife.