FWS tacitly accepts massive damage to
Everglades
Background.
Since 1993, water managers have dumped historically unprecedented amounts of water into the western part of the Everglades — and not the East, which is the natural flow path. In doing so, they have destroyed the natural vegetation over nearly 1000 square kilometers in the West, leaving the eastern Everglades too dry and prone to fire. What has limited their ability to do more damage, has been the Federally listed Cape Sable sparrow. In the past, FWS has made it clear that the western populations of this bird were essential to its survival. Indeed, a year ago, the FWS declared these western populations to be in Critical Habitat — a designation that helps protect the birds and the habitat. Now, apparently bowing to political pressure, they have changed their minds.
Last week's final
designation of Critical Habitat for the Cape Sable Sparrow excludes the vital
western population. The decision
is inept, it ignores peer-reviewed science, yet embraces wholly unsupported and
unavailable documents speculating on possible future and past scenarios, and
includes a trite economic analysis.
By reversing its
earlier sensible proposal, FWS's revision tacitly accepts massive damage to
nearly a thousand square kilometres of our most important wetland national park
and risks the extinction of a federally listed Endangered Species. While
others have discussed the decision's likely political motivation, my
contribution is simply to conclude that it cannot be considered a credible
document.
The final designation of Critical Habitat for the Cape Sable Sparrow is inept, ignores peer-reviewed science, embraces wholly unsupported and unavailable documents speculating on possible future and past scenarios, and includes a trite economic analysis. By reversing its earlier sensible proposal, this revision tacitly accepts massive damage to nearly a thousand square kilometres of our most important wetland national park and risks the extinction of a Federally-listed Endangered Species.
Since 1992, I have been, and continue to be, the principal external scientific investigator of this species. Former students, Dr. Julie Lockwood, Dr. Clinton Jenkins, and Dr. Gareth Russell, also work on this species.
In late 2006, the U.S. Fish and Wildlife Service (FWS) issued a proposed designation of Critical Habitat for the Federally-listed Cape Sable Sparrow. I saw no need to comment.
The final rule released on November 6th is more seriously flawed than any decision I have ever seen, in a career working on endangered species. It includes the smaller, fragmented populations east of Shark Slough, but now omits vital areas west of the Slough included in the earlier proposal where
ItÕs rather like giving the military the mission to protect and serve our nation, Òbut by the way, New York, Los Angeles, Chicago, and all the other big cities arenÕt critical, just concentrate on rural Nevada.Ó
Although the sparrow was first found on Cape Sable, only a few birds were present and the extent of the habitat meant that the population was always likely to have been ephemeral. Had it not been found there, it would have likely been called the ÒWest Everglades sparrowÓ because from the 1920s until the early 1970s, it was known only from areas west of Shark River Slough — the very areas not included in the Critical Habitat. (Populations were found east of the Slough in the early 1970s, though likely they had been there earlier.)
When standard surveys began in 1981 to 1993, roughly half the sparrows lived west of the Slough!
This changed from 1993 onwards, when water managers released historically unprecedented water flows across the water control gates, which are due north of these western sparrows (the S12s), flooding them during the breeding season, and destroying ~95% of the birds in the area. While breeding season water releases through the S12s were eventually curtailed, equally unprecedented water releases to the west of the S12s started in 1994 and continue to this day. These flows exterminated the species from its ÒheartlandÓ in the south and central part of its western distribution.
Simply, the low numbers of this western population, not now within Critical Habitat, cannot be attributed to the populations their being ephemeral, isolated ones. Rather, the western sparrow population was large, persistent, and destroyed by poor water management choices, not Mother Nature.
This isnÕt just about the sparrow. Poor management choices have destroyed perhaps 50,000 hectares of mixed prairie, the sparrowÕs preferred habitat, and one of the most floristically rich plant communities in the Everglades Ecosystem, turning it into a much less diverse sawgrass marsh. An entire ecosystem has been harmed. Worse, Everglades restoration requires water flows to be moved to the east — along the SloughÕs natural and historical flow path. This Critical Habitat rule accepts unnaturally high water levels in the West (where they do not belong) while keeping the areas east of the Slough unnaturally dry and so prone to fires.
The justifications for the final rule excluding the western population are unconvincing.
Based on pollen samples, the rule makes the extraordinary claim of the west being pure sawgrass marsh historically — and so being unsuitable for sparrows before their discovery nearly a century ago. Well, mixed prairies today do contain some sawgrass. Indeed, in patches, it may dominate. One cannot infer the large-scale vegetation patterns based on few small samples, however. The authors of the key paper say that! FWS bases its rule on a sloppy reading of just one scientific paper, likely finding the result they desire, and ignoring all that paperÕs caveats.
The rule suggests that according to some models, restoration will make the western populations wetter. Those models fall so short of external review as to be quite literally incredible. I have repeatedly asked the FWS to provide maps of where water will be at given times of year, under these restoration scenarios. The scientific community is still waiting. The few maps we have seen deviate so badly from known water depths that we think it is unlikely that those who produce them will ever find it possible to publish them. To be brutally frank, modellers should put up or shut up. One should not base management decisions on speculations that cannot handle scientific scrutiny.
The economic analysis is simply silly — exactly as Dr. Rich Weisshoff (an author of economic analyses of Everglades management actions) has spelled out. My one paper on ecological economics (in Nature and well-cited), points out that economic analyses are often too constrained. In this case, a sensible, complete analysis would have noticed that the sparrow provides the cheapest, large scale (Everglades-wide), regular (annual), and fine-scale (< 1 km2) biological assessment of the EvergladesÕ mixed prairies. Such an assessment would be more expensive without the sparrow. It saves, not spends money.
There is widespread discussion on the political reasons why the FWS have reversed its earlier proposal. The first proposal was based on sound science, published in prestigious peer-reviewed journals; this one based on mere speculation.
The views in this document are mine and mine alone. I can be reached at (646) 489 5481 (cell) and StuartPimm@aol.com.
Key documents are on my website http://www.nicholas.duke.edu/people/faculty/pimm/cssp/
In addition, please notice the text of the 1999 Recovery plan, which called for a revision of the 1977 Critical Habitat. HereÕs the exact quote.
ÒCritical habitat for the Cape Sable seaside sparrow was designated on August 11, 1977 (50 CFR 17.95), before the full distribution of the subspecies was known (Figure 2). The critical habitat, as designated, does not adequately account for the distribution of the present-day core subpopulations, or the areas necessary for continued survival and recovery. An important area west of Shark River Slough, which until 1993 supported one of two core subpopulations (nearly half of the entire population), is not included within the designation, and has been undergoing detrimental changes in habitat structure as a result of water management practices. Additionally, other parts of the designated critical habitat have been converted to agriculture, and are no longer occupied by sparrows. Thus, Cape Sable seaside sparrow critical habitat requires significant review and redesignation. When redesignating critical habitat for the Cape Sable seaside sparrow, it will be important to include all potential habitat necessary for recovery, including areas not recently utilized by the birds. This will help to protect habitat for future expansion of existing subpopulations and provide for the natural variability associated with the Everglades ecosystem.Ó
The suit to obtain the critical habitat revision was entirely driven by the plaintiffs desire to implement this portion of the recovery plan. The judge ruling on the case expressly pointed to this passage as requiring the revision. The proposed rule follows the plan. Now the final throws it away.