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Unquestionably, the vast majority of these deaths were caused by “accidental” drowning from being caught in coastal gillnets and shrimp trawl nets (Shanker & Choudhury 2006). For example, on February 17, 2002, 205 dead olive ridleys entangled in a single section of gillnet were washed ashore at Gundalba Beach, Orissa (Wright and Mohanty 2002). Gopi et al. (2002) reported that mortality due to mechanized offshore fishing reached an “alarming number” of 14,000 turtles in 1998. During a study of sea turtles in Orissa, Pandav (2000) counted 46,200 stranded adult olive ridleys from 1993 to 1999. In the words of Gopi et al., “These 46,200 turtles were counted only in a stretch of 282 Kms out of the entire 480 Km coastal belt of Orissa. Hence, the actual number of dead turtles would relatively be much higher without any doubt.”

But these turtle deaths, past and present, are not accidental. Much of that mortality could and should have been prevented using a two-decades-old existing and proven conservation-fishing technique (using turtle excluder devices—“TEDs”) and simply enforcing existing fishing regulations. Years of studies by the U.S. National Marine Fisheries Service prove that TEDs are consistently 97%-98% effective at releasing trawl-caught turtles (J. Mitchell pers. comm.). Studies conducted by the Orissa Government Forest Department and the Wildlife Institute of India off Orissa beaches during high-turtle-density arribada months showed that TEDs worked very effectively there (“The Central Institute of Fisheries Technology - developed TED excluded 100% of turtles”) and “catch loss (of shrimp and bycatch) was very minimal” (Gopi et al. 2002).

Ominously, the conservative estimate of 10,000 annual bleached and bloated carcasses on Orissa beaches represent just a fraction of the total number of sea turtles being killed by the shrimp and gillnet fisheries there (and probably elsewhere in India). A stranding study conducted off the United States’ East Coast to estimate the quantity of sea turtles affected by the shrimp trawl fishery released dead, marked sea turtles at offshore, shrimp trawling grounds. Only 6 of 22 tagged loggerhead carcasses released at sea turned up as beach strandings (Murphy & Hopkins-Murphy 1989). Another study showed that marked turtles that ultimately stranded made up just 7% to 13% of the total marked turtles released (Epperly et al. 1996). The prevailing ocean currents and winds carried most of the bodies seaward, rather than shoreward where they could be observed and counted. So these, the majority of drowned turtles, are not seen or counted. In other words, those 100,000 observed carcasses on Orissa beaches are likely just the tip of the “mortality iceberg” caused by shrimp trawling and gillnetting. Scientists hate to speculate and surmise, but this is probably a very safe bet—a whole lot more turtles are drowning than are being counted.

This level of mortality over the long term on a population is simply unsustainable. Bad things are going to happen. We’ve seen it before (La Escobilla) and we’re seeing it elsewhere as well (Terengganu). We all know that sea turtles take many years to reach sexual maturity (olive ridleys may take 10-18 years before they reproduce, according to a recent study (Zug et al. 2006); the range commonly given is 7-15 years), and produce just 110 to 330 eggs per nesting season. It is not known if they nest annually, but the number of “generic” sea turtle hatchlings that reach adulthood has been estimated by sea turtle scientists at about 1 in 500 hatchlings (U.S Fish and Wildlife Service Web site; R. Mast pers. comm.), though various sea turtle conservation Web site estimates range from 1 in 100 to 1 in 10,000 depending on your source. The 1 in 500 estimate is obliquely supported by the 1990 U.S. National Academy of Sciences’ report (Decline of the Sea Turtles: Causes and Prevention) which stated that, for loggerheads, each individual breeder’s reproductive value is estimated to be about 584 times greater than that of an egg or hatchling.

Already, warning signs are appearing in the Gahirmatha sea turtle population. The average size of stranded turtles and nesting females turtles has significantly decreased in recent years, according to scientists at the Wildlife Institute of India (S. Kumar pers. comm.) and other researchers (Shanker et al. 2003; Plotkin 2007). Could it be that the largest sea turtle size-class—the one longest exposed to trawlers and gillnet—has already been culled by drowning? (That is not untypical of collapsing fish populations—one of the first signs of trouble is that the larger fish have disappeared; they’ve all been caught.). As well, the number of dead sea turtles observed stranded on Gahirmatha beaches has been decreasing in each of the last (approximately half-dozen) years according to another noted Indian sea turtle biologist (C.S. Kar pers. comm.) of the Orissa Government Forest Department—a possible indication that fewer turtles are being impacted by trawlers and gillnetters. This latter observation is chilling, since neither beach monitoring effort nor trawling or gillnetting efforts have decreased. In fact, reports suggest an increase in fishing intensity from less than 1,000 mechanized boats in the late 1980s to more than 4,000 boats by 1996 (Shanker et al. 2003). The conclusion? Fewer turtles are arriving offshore to mate and nest. No arribadas occurred in Gahirmatha in 1997, 1998, or 2002, “which is the highest incidence of failure in the documented history of this rookery” (Shanker et al. 2003), nor was there an arribada in 2008. Happily, it did occur this year, commencing on March 21st, and Orissa Government Forest Department’s official nesting estimates are of 1.7 lakh (170,000 turtles) during the week that followed (B. Bhuta pers. comm.).

Some of the preceding observations may by themselves mean nothing: Arribadas may be cyclical and may be influenced by wind, tide, lunar phase, and other unknowns. Nesting beaches may be significantly affected by beach erosion (and beach accretion), and may wax and wane naturally over time. Certainly the size and availability of a suitable nesting beach plays a role in a sea turtle nesting (or not) at a particular site. Nayak (2003) opined that the primary reason for missed arribadas at Gahirmatha is beach erosion resulting from the geomorphological changes undergone by the Nasi Islands (where most nesting takes place). A study conducted by Prusty et al. (2006) to assess the factors leading to the non-occurrence of arribadas at the Gahirmatha site indicates that the nesting beaches in Gahirmatha are eroding at a faster rate over the years. A study by Choudhury et al. (2008) based on monitoring the changes in the Gahirmatha nesting beach profile from November 2007 to May 2008 reveals the changes in the beach profile as a very strong reason why arribadas may not be taking place there. Meanwhile, without evidence and because it is an easy target, some no-doubt-well-meaning conservationist fingers are being pointed at Dhamra Port dredging as the reason for Gahirmatha’s beach erosion and reduced nesting, disregarding the fact that the dredging is a relatively recent phenomenon (it commenced in November 2007) and erosion of the Nasi Islands had been occurring for years before dredging commenced. Will dredging have some effect on erosion rates at Gahirmatha? Maybe. Probably it will affect the nearby mangroves. Will actual dredging kill turtles? Very few. The complete truth about dredging effects on the Gahirmatha rookery will be elusive and may be forever obscured in accusations and counter-charges, and even well-designed studies may prove inconclusive—but let’s not disregard the basic known fact: A huge turtle toll is being continuously taken by local fisheries. This alone should loudly sound the alarm bells for Gahirmatha.

Shanker et al. (2003) concluded in 2002 that Gahirmatha has had no drastic decline in the nesting population over the last 25 years, but that the Orissa population is “clearly of imminent conservation concern.” That conclusion is seven years old—seven years of unrelenting, day-in, day-out, fishing pressure on Gahirmatha’s olive ridleys. Approximately 70,000 to 700,000 turtles have been drowned by Orissa fishers since then. To put it another way, that’s about 30 to 300 turtles a day, every day, since 2002, using the irrefutable, minimum number of 10,000 known, observed strandings per year.

The scientific method is good: To our credit, most scientists adhere/cling scrupulously to it. We are prudent and cautious, analytical and measured. No one will ever accuse us of jumping to conclusions: It’s what sets us apart. It’s necessary to remain dispassionate, objective, unjaundiced, skeptical: Scientists generally cannot/should not get emotional, outraged, incensed, or vitriolic, for risk of appearing less-than-objective. However, sometimes our aloofness works to our detriment. Sometimes it’s good—even necessary—to get mad, indignant, horrified, outraged. Certainly the carnage at Gahirmatha merits that reaction. It’s time to blow the horn loudly for Orissa’s sea turtles, but let’s focus our anger and concern at the main threats, not the red herrings.

In the face of uncertain times and warning signs, even the public—the most common fellow on the street—is instinctively conservative. So where is our (the sea turtle scientific community) collective sense of outrage? Where is the Indian Government’s (and State of Orissa’s) sense of caution, prudence, conservatism, and responsibility? Where is law enforcement of existing TED regulations? There’s a large military presence and Defense base (of the Indian Defense Research and Development Organization) on Outer Wheeler Island, just minutes away by boat from Gahirmatha Sanctuary and Bhitarkanika Sanctuary and National Park. There is also a Coast Guard Base at Paradip at the southern end of Gahirmatha. Can’t the Defense Organization/Coast Guard patrol for TED compliance, and to keep gillnetters out of Sanctuary waters? Can the solution be so simple?

Someone in authority (i.e., State and Federal Government ministries) has got to get some courage and step to the plate. Maybe the United States and other signatories to international sea turtle conservation agreements should get together and apply diplomatic pressure. Meanwhile, a smart-looking, seaworthy patrol/research vessel of the Orissa Government Forest Department—aptly named Olive Ridley—lies mostly idle, tied up at its Dhamara Fishing Harbour mooring, while TED-less trawlers daily motor out past it, heading out to sea, where they continue to drown staggering numbers of sea turtles yearly. It simply cannot go on, biologically or morally. Sea turtles in India supposedly enjoy a “Schedule 1” protected status, the highest status/level of protection given by the Wild Life (Protection) Act of 1991. Where is public outcry? Surely, the situation is egregious, outrageous, and shameful. It smells, literally, of rotting sea turtles.

The Indian Government, at both a Federal and State level, can and must attempt to make significant progress towards halting the largely preventable slaughter of olive ridley sea turtles in Gahirmatha and other Orissa coastal waters. This should be done before India hosts the 30th Annual International Sea Turtle Symposium in Goa next February. That, more than anything, would truly send an international message of sea turtle conservation. To do otherwise would appear very irresponsible and two-faced, at least to the present writer, and perhaps to the world.

¹The opinions presented herein are my own and not necessarily those of my employer.

CHOUDHURY, B.C., A.K. NAYAK, K. SIVAKUMAR, C.S.KAR & S. BEHERA. 2008. Determining the offshore distribution and migration pattern of olive ridley sea turtles (Lepidochelys olivacea) along the east coast of India. Wildlife Institute of India (unpublished data cited in abstract by S. Behera: Has the Gahirmatha Olive Ridley sea turtle rookery become nonconducive for future arribada?

GOPI, G.V., B.C. CHOUDHURY & B. PANDAV. 2002. A quantitative analysis of incidental capture and mortalities of sea turtles during commercial shrimp trawling using Turtle Excluder Device (TED) along the coastal waters of Orissa. Wildlife Institute of India, P.O. Box # 18, Chandrabani, Dehradun-248001.

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PLOTKIN, P.T. (Ed.). 2007. Biology and Conservation of Ridley Sea Turtles. The Johns Hopkins University Press, Baltimore, MD.

PRUSTY, B.G. & S. Dash. 2006. The effect of rookery geomorphology on olive ridley nesting in Gahirmatha, Orissa. In: Shanker, K. & B.C. Choudhury (Eds.). Marine Turtles of the Indian Subcontinent. Universities Press, Hyderabad, India pp. 384-392.

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SHANKER, K. & B.C. CHOUDHURY (Eds.). 2006. Marine Turtles of the Indian Subcontinent. Universities Press, Hyderabad, India. 415 pp.

U.S. NATIONAL ACADEMY OF SCIENCES. 1990. Decline of the Sea Turtles: Causes and Prevention. National Academies Press.

U.S. FISH & WILDLIFE SERVICE. March 31, 2009. <http://www.fws.gov/northflorida/SeaTurtles/SeaTurtleBrochure.pdf>

WRIGHT, B. & B. MOHANTY. 2002. Olive ridley mortality in gillnets in Orissa. Kachhapa 6:18.

ZUG, G.R., M. CHALOUPKA, M. & G.H. BALAZS. 2006. Age and growth in olive ridley sea turtles (Lepidochelys olivacea) from the North-central Pacific: a skeletochronological analysis. Marine Ecology 27:263-270.