Tuesday, February 11, 2014

How to dispose of dead stranded whales?

Ini adalah versi bahasa Inggris dari artikel tentang cara membuang bangkai paus yang sudah mati. Klik tautan ini untuk versi bahasa Indonesia-nya.

The sperm whale stranded at Central Sulawesi on 4 Feb. Source: local govt of Central Sulawesi

Well, actually not only whales, but also dolphins, porpoises, dugongs. In general, the question of what to do with dead stranded marine mammals is a frequently received question, particularly since a few days ago when a 18m sperm whale stranded at Morowali Beach, Central Sulawesi. Naturally, dealing with small cetaceans and dugongs is easier than trying to dispose of a whale, as you would read below. But let’s start from the beginning.

Approximately on 4 February 2014, a Code 3 (dead, starting to decompose) sperm whale stranded at Morowali Beach, which practically is in the middle of nowhere in Central Sulawesi. Since the government and the people weren’t sure what to do, they left it until Friday, 6 February before contacting us at Whale Stranding Indonesia. Since the animal was dead anyway, and from the picture it was already Code 3-4, we skipped the necropsy suggestion (by the time the necropsy team arrives, it would have been late Code 4 anyway). 

We suggested sample collection instead for genetic analyses and – if possible – toxicology. We asked the local government to collect the tiny tip of the dorsal fin (or any fin, or the meat) and store it inside 70-100% alcohol. We also asked them to collect the blubber, if possible (as in, if the blubber wasn’t decaying yet). Also important, we asked for photographs and morphometric measurements (total length and girth of the body). The local government texted us the photographs and measurements (I love Whatsapp!) and collected the meat, to be later sent to the Indonesian Biodiversity Research Center (IBRC) Denpasar and LIPI Jakarta for genetic analyses. Yes we know it’s a sperm whale, but it would be nice to confirm its sex. Besides, it’s always useful to have the genetic sequences of sperm whales in Indonesia, to determine whether they are part of a unique population, etc.

All possible samples collected, the next question is (naturally), what to do with the bloody carcass. Even a small decaying dolphin is stinky. A whale that big is certainly much more stinky and unpleasant to deal with. Geraci and Lounsbury [1] cheekily noted that “[t]he simplest way for a carcass to disappear is to turn your back on it and walk away.” They do admit that such approach is “fine in remote areas, but what if the scene is a bathing beach or someone’s backyard?” 

Geraci and Lounsbury [1] then listed seven carcass disposal methods available: 1) let it lie, 2) bury it, 3) move it, 4) tow it out to the sea, 5) render it, 6) blow it up, or 7) burn it.  Geraci and Loundsbury didn’t recommend sinking the whale, for it would be technically difficult (a whale with Code 3 and beyond would be too buoyant to sink). However, friends from the Jakarta Animal Aid Network and She Dives (a group of Jakarta-based cool female divers) used the sinking method to dispose of a dead sperm whale in Seribu Islands, back in September 2012. The method worked, and I will discuss it later below. 

The followings are three major techniques for carcass disposal applicable for Indonesia, with its pros and cons:

1. Burn it 
Pros: good to dispose of large whales. Burning is a relatively safe and fast process, although the burning time is still quite significant for large whales.

Cons: we lose the skeleton for educational or future research purposes. The smell of burning flesh can be overwhelming, tho not as bad as the smell of decaying carcass left behind.

2. Bury it

Pros: easy for small cetaceans and dugongs. We can keep the skeletons later for educational or future research purposes. For large whales, we need at least 2 meters of grave above the tidal line. If not, see the cons below. If you bury it for later excavation, make sure that no one is going to pour cement on top of it to make it a beach parking lot or the like. This one really happened to Bob Brownell who meticulously dissected a pilot whale and then buried it at the edge of a parking lot of the Cabrillo Beach CA (“The next spring, without notice, the city’s road department sent a work crew to improve the parking lot, which they did. They extended it, graded it, then paved it over – whale and all” [1, p. 232]).

Cons: Pretty hard for large whales. Need big tomcats/excavators to dig and bury the whale, hence can be pricey. It may take more than a few hours to bury the whale too. If not buried deep enough, it might still attract terrestrial and marine scavengers. Even if it’s buried deep enough, the seeping oil may still attract sharks (see this link). There is also a possibility that “a carcass that is rich with blubber will tend to rise in soft wet sand, even when split open and weighted down with tons of rocks” [1], which happened to four humpback whales buried just below the tidal line in sandy beaches around Cape Cod (USA). The whales resurfaced twice in a year and had to be reburied. Yuck.

3. Sink it

Pros: anti-scavengers (except for the varanus, see below). If the carcass is wrapped with fishing nets before sinking, and the location is well-marked, the skeleton can be retrieved later for educational or future research purposes. Make sure that the whale is towed from the tail, not head, otherwise it would go nowhere, as witnessed by my former supervisor Helene Marsh who attempted to tow a dead minke whale head first (“Its mouth opened and acted like some giant sea anchor. The trawler was going absolutely nowhere” – [1, p. 234]). To prevent the whale from floating back, the whale needs to be deflated by shooting the whale stomach with long range gun to release internal gasses. The use of long-range gun is preferable to sharp, but short-range weapons such as a knife or glaive because the gases inside can explode in such a nasty way, and the glaive wielder can be exposed to nasty explosion and decaying materials, which is definitely unhygienic and potentially dangerous.

Cons: need a ship or tug boat to tug away the carcass, hence can be pricey. The underwater position of the carcass can shift with currents, hence can be difficult to find.

The Balinese burned a humpback whale stranded in Tabanan, Bali in October 2007. It took more than half a day (not sure how long actually), but it was considered an effective way of carcass disposal in the light of no heavy machineries for burial. 

The cremation of a dead humpback whale in Bali. Published at the Raffles Bulletin of Zoology 2009 vol 57 issue 1
The government of Morowali and Sulawesi in general tried sinking the aforementioned sperm whale into the sea. They dragged the whale offshore and released it. I’m not sure if they put weight on the whale, but the carcass was washed back ashore. Later I realized (thanks, Nimal Fernando of Ocean Park Hong Kong for reminding us!) that the whale floated back because it was already buoyant with intestinal gasses. Again, deflating the whale with long-range gunshot is recommended to avoid floating back. Avoid using sharp weapons like knife, spear or glaive because they are still short-range weapons. The user will still get most of the explosion, should the whale explode (and it’s very likely, see this video).

Back to the sinking method. It was used the first time in Indonesia by the Jakarta Animal Aid Network (JAAN) and She Dives on a dead sperm whale off Kotok Island, Seribu Islands. Back in September 2012, they used proper weighs and fishing net to sink the whale not far offshore. The method actually worked. Three months later, they ‘fished out’ the skeleton, clean and ready to assemble for museum display, thanks to the presence of a helpful Varanus (water lizard) that ate away the flesh while the carcass was underwater.

What about blasting/blowing the whale up or relocating the whale elsewhere?

Blasting the whale is NOT recommended because it’s dangerous for the technicians and also unpleasant for the people (you really don’t want to have pieces of smelly stinking whale meat landing on your lap, vehicle or passenger compartment). See this awesome clip of a ‘very successful’ attempt to blow up a dead stranded whale back in 1970 at Lane County Oregon in the USA (reporter Paul Linnman’s accent reminded me of Alan Ladd and other Wild West movie actors…). After the explosion (which turned out to be a very comical disaster), the seagulls (that were expected to scavenge the whale remains) were nowhere to be seen, undoubtedly “permanently relocated to Brazil” [1, p. 236].

Shipping the dead whale to a research facility can be troublesome as well. In 2004, a sperm whale washed up on the coast of Taiwan. After days of discussion (we humans are very good at delaying important decisions!), the whale carcass was finally transported to a research facility in a nearby city of Tainan. However, before reaching the research compound, the whale self-detonated itself, showering the street and vicinity with its blood, gore and other smelly materials.  

Below are the embedded versions of the three very inspirational video of what NOT to do with a whale carcass (viewing while eating is not advisable): 





1.            Geraci, J.R. and V.J. Lounsbury, Marine Mammals Ashore: A Field Fuide for Strandings. 1993, Texas: Texas A&M University Sea Grant College Program.

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