. and Gas Development in Western North America: Cts oIiSagebrush Steppe Avifauna Particular Emphasis on Sage GrouSe

·t E. Braun . radoDivision o/Wildlife . t Collins

mi'ng Game and Fish Department /tette

;t~anieron L.Aldridge ':'rf;niversity a/Alberta. ::'Biftrtonton

Transactions of the 67th North American Wildlife and Natural Resources Conference fi 337

of these species. are now known or thought to· be declining in "'~"""'~\!,,\! abundance.

OHand gas developments and their attendant structures, . lines, roacts and collection stations, are not recent· additions to· America~ since some activity dates to the late 1800s. development activity tends to be cyCliCal, depending on extraction coSts and cost pet barrel or cubic foot. In the 1970s the interest was in development of oil shale. In the early and emphasis was in the Rocky Mountain Overthrust ;Belt . Today, arid gas development is everywhere in the West, where reserves be present. Nowhere is this more aPl?arentthari in development methane, especially in the area near Gillette,. Wyoming. Because

. . . expansion and .development of oil and gas. reserves; this paper is known about the effects of energy exploitation on sagebrush avian. species and logical expectations during. and· after development and extraction. Case history examples are provided Colorado and Wyoming.

Wbat.IS KnoWn

Atelativelylatge body of literature exists for game sage~grouse (Connelly .etal. 2000) and Columbian sharp.,.tailed and Connt!liy J993). Reasonable information is av~lable for breeding in sagebrush steppe and the presence of sagebrush 1972; Schroeder iiildSturges 1975; Reynolds and Rich 1978; Reyilblds 1981;· Peterson and Best 1985a, 1985b, 1987) and (Rotenberry and Wiens 1980; Wiens and Rotenberry 198 I, 1985; 1987; Knickand Rotenberry 1995; Aldridge and Brigham 2002) for all sagebrush obligates. Relatively little is known about the alteration oiHitherspeeies,sllch as burtowingowls and mountain seasonally occupy the interface of sagebrush steppe and 151a""u •• uuo:>,

that burrowing owls arenegativcly impacted by plowing, n::~;t:l;«lf' disturbances in breeding areas (Rich I 986t Harig etal. 1993). habitats to reseed with taller grasses also has negative effectS plovers, and restrictions have been placed on oil and gas breeding areas in Colorado, Montana and Wyoming (Knopf 1996),

338 ~. Session Five: Oil a1ld Gas Development in Western North America.,.

Review of the available information suggests that habitat alteration removes live sagebrush and reduces patch size has negative effects for all

obligates, specifically sage-grouse, sage sparrow, sage thra$her and sparrow. Plowing of native habitats is also negative for burrowing

and mountain plovers. Columbian sharp..;tailedgrouse (and other are less impacted, as they can positively respond to some altered

· . providingtbatriative shrub habita~remainavaiiable. Thus, sbarp­grouse have the best potential to maintain their distribution and abundance

. changes in habitat use and disturbance.·

• and· Gas Developments and Sage-grouse

Sage-grouse were historically abundant across southeastern Alberta, as much as. 18,920 square miles (49,000 km2) in the t:(arly 1900s

2000). However, the current dlstdbutlon of sage:-gTousehas been · . to approximatelyl,544 square ritiles (4,000 km2), less than 10 percent · . historic range. Sage:-gTouse population data exist for the currently

area; however lek counts oilly began in 1968 and were conducted

""_._~ •• J prior to the 1990s. Thus, direct comparisons and cause-and-effect are not possible, but the availaQle data are cornpeillng, .

Records of oil and gas developmenrsare incomplete and difficult to but the earliest records suggestthatexploration for gasbegari as early

The oil boom of the mid;.1980s resulted in intensive oil extraction

in southernAlberta~ • Over this time~ the number of male sage-grouse at lek sites decreased from as many as 524 niales to as few as 300

2000). Similar correlations were seen in the early 1990s; with a nglenc:e of development activity in the heart ofsage..:grousehabitat

tSmJh .. ·1Ti,3<: Oil Field}. The number of male sage-grouse in Alberta fell to the

known level, with only 70 males in 1994 (Aidridge 20(0), Direct irbalnCI~S (development of road or well sites ) within approximately:120 Yards

. .of three different lek complexes were noted between 1983 and 1985. of these leks has. been active since the disturbance. At that same time,

activities occurred within view of a fourth lek complex and the two lek . were reduced to one smaller lek;This site bas since been reclainied,

Two additional known .lek sites were

\'ji}[;iwUiactjiOns of the 67'h N(mhAmeric(JTi Wildlife and Natural Resources Conference "t.l. 339

directly disturbed at some unknown time in the past; one is now a reclaimed;l weBsite and the second was seeded to tame grass;the latter. most likely, is alsQ a reclaimed well site. Neither of these leks have beeilactive for at least lOyearS~i

To date, approximately '1,500 wells have been drilled within the CUrrent range of sage-grouse. in Alberta. It is estimated that 575 wells are still producing.! Thus"there are approximately eight well sites per square mile (one active alltt two inactive well siteslkin2) within sage-grouse habitat.Corm:ectiIig each ot::, these well sites is a series of roads and trails, as well as power linesand pipelii1es~\ that are interlaced with compressor stations and gas c~ps. These structures if and linear features result in directhabhat loss and fragment remaining suitable? habitat. The effect of daily vehiCular traffic along these road netWorks can also", impactbreediilg activities or directly reduce survival. ,;f,;

There are relatively few limitations placed on spacing and density o{,t well sites in Alberta., Each company is restrh:;ted to drilling 16 well sites per'~ section of hirid, but each is al10wed '16 weIJs per zone in which they are drilling, A Thus the total number, of wells potentially could exceed 16 per section~,i Recommendations andgtiidelirtes are made by the Alberta Department of Fish) and Wildlife to reduce the impact of snch intensive drilling, particularly in": important sage-grouse habitats~ 'However, there is no current legisi~tion that,~ commits Alberta Public Lands or' the Alberta Energy Utility • Board to these:l~ recommendations. Under the Alberta Provincial Wildlife Ad. an iridividual~l cannot willfully destroy the nestor den site of an endangered species: sage-j grouse are listed as endangered in Alberta and Canada. This provincial~i

, legislation offers little or no protection for sage-grouse breeding and nesting;~ habitat; and, currently, there is no federal legislation in place.'~'

Over the last three decades, the Alberta sage-grouse popUlation hlis}' declined by at ieast 66 percent (Aldridge 2000). Currently, only seven of 3J:;[ hist,oric lek comple:x:es remain active. The future plans for oil and gas A:: developments within the range of sage-grouse are unknown, but expansion i~'~\ expected. The cumulative impacts of further activities could result in reductiOn f~1 of the Albertasage-grousepopulatiort to non-viable levels.'~i , Colorado :~@l

Sage-grouse historically occurred in at least eight countiesinColomdo:i:~ (Braun 1995) in whiChoil and gas development is common. No cause.:.and;~;

, , '0 effect studies have explored the impacts of oil and gas production on sagl>' 1

340 " S",/on Fl." Oi/and Go, n."Jop~", .. W'n,m N,!rtb Am"u.o...:1

W." ~" "

grouse populations, although. Braun (] 987 •. 1998) generally discussed. the apparentshort-:tenn impacts. Presently, active oil and gas production occurs in only four counties (Jackson, Moffat, Rio Blanco and Routt),while sage~grouse populations within areas impacted by coal bed methane (CBM) production (LaPlata and Montezuma) or that could be potentially impacted by development of oil shale (Garfie1d) are no longer pres~nt.due to complex factors.

Oil and gas developments preceded formal counts of sage:-grouse in Colorado and date· to at least the· early 1920s. Counts of sage-grouse were initiated on a sporadic basis in Colorado in the late 19405.· These counts were incoinpleteand focused on larger, more accessible leks. Thus, data collected from the 1940s to the early 1970s are not directly comparable to those collected in the last 25 to 30 years. Therefore, it is not possible to be defillite about actual impacts of oil and gas deve!opmenfon sage-grouse.

The most cornpletedatasetfor sage-grouse arid oil and gasprdduction is from North Park, in JncksonCounty;Deve]opment oftheMcCallum Field was initiated in 1926, and it continues to be active, with 47 producing wells; 39 water injeCtion wells. 25 abandoned (plugged) wells arid six approved plans for we1lsinart areaM approxiniately8,600 acres (2;125 ha) .. This area has a well~developed unimproved road network, with one paved toad to a processing plant,numerous pipelines and ifewpowerlines. Sage~grouse werereported to occur in· the McCallum Field in the 1940s hutno data are avaiiable. • DurIng the ]973 to 2001 interval, at least lilekswere active within orimmediately adjacent to the McCallum Field. Seven of these leks were active i0200 I, with a total of 181· maJes, which is 12.8 percent of the. total males counted on 20.6 percent of the active leks in North Park. Examination of eachactlvelek indicated that only two were within sight of an active well or power line; Most were out of sight because of topography, but there· were noises associated with pumping and oilfield activities inaudible to the hi.lInanear~ mi the leksite. Only three active leks were within the main oil field and 8· of II· known lek sites were on

, the periphery. During the 1973 to 2001 interval, the number of male sage­grouse counted and active leks in this area fluctuated in synchrony with the entire sage-grouse population in North Park. Sage-:grouse are also known to

, winter within the McCallum Field (Beck 1975) becailSea series of ridges are , wind swept of most snow. .

Locations of the known active sage·grouse leks in the McCallum Field i suggest selection for sites that are removed froin disturbance.s; such as actjve

Transactions oj the 6?h North Amerkan Wild/tfe aM Natural Resources CiJfljereflce 14: 341

wells, the processirigplarit, the paved road andpowerlines. The Field is a relativd y small, old, moderately developed oil production deri10nstrates that sage.,.grouse continu~ to use areas in and near oil . facilities providing that suitable· sagebrush-domiriated habitats are and that they have opportUnity to select sites tha,t are not disturbed by structures or paved roads. Despite the· fragmented nature of the trails, pipelines, power lines and several roads) in this area,only are·no longer use.abJeby sage-grouse.

Wyoming Oil and gasdeve1opmetttinWyoming dates to at least.to 1 •.

Creek Field). Since that time, many additional 011 and gas. fields discovered and developed througtiout areas occupied by sage~grouse. the focus is . on development of CBM in northeastern Wyoming .. development, in northeastWyoming. began iIi 1987 with a test welL next 10 years. mote wells were drilled and markets were developed From 1997 to 2001, nearly 12,000 CBM wells were brought into Another 46,000 welis are expected to be developed withiri the Basin over the next 10 years,according to the BUreau of Land · (BLM) Draft EISforthepowder River Basin Oil and Gas Project .80 percehtof the production to date occurs on private surface iands remainder onstate-; 13LM.,.,anq US Forest Service- (USFS) owned half of the· mineral ownership within the· basin is private. CBM • invol vesdrilling relliti vely shallow water wells into the coal seams · the water and release the gas. The gas is then sent through a series of stations and finally released into large tfansportationpipelines· Discharge water is either impounded locally. or released into area Each weli has· at least one uniinproved road, an electJi.calline, a and a water discharge pipeline. Forevery sixto 10 wells, there is stage compressot~ Larger, two:-stage compressor stations arebllilt . three to five smaller compressor stations and there is a large facility stage gas compression. All facilities have improved road access, overhead power lines and underground pipelines. The expected life of a CBM well is about seven years, depending upon the depth seam and the amount of gas present. With an estimated 25 trillion CBM within the Powder RiverBasin,the life of the devdopment is

342* Session Five: Oil and Gas Development in Western North America ...

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I~; be 30 to 50 years. Prior to 2001, weils were drilled with40~acre (16 hal spacing. g~:Currently, wells are drilled with 80-acre (32 ha) spacing, however exceptions l' to this rule are often granted to facilitate production. The disturbance· from iF .. pipeIines, power lines .and roads is similar with either well.:.spacing criteria .

• Although the actual disturbed area from wens, compressors, pipelines and roads l~relatively slIlal1(typically I 5:-20 acres [6-8 hal per section), the overall project -&rea is very large andmostlycoritiglioiIs: . Crirrently, the 12,000 active wells Qi;cur.over an area .of approximately 4,500 square miles (11,655 ~m2) .. The iotal field development area is approximately I I ,000 square miles (28,490 kJn2), which win result in a totai of over 3()O,000acres(121,4IO ha} in direct habitat loss .. Predomiriate habitats within the CBM devdopmentaieainclude sagebrush and gtasslandtypes, agricliltutallands (hay arid grain fields)a:rid some mixed

b communities. Most of the area is considered yearlong sage-grouse habitat. with over 200 known active leks. Not all oOhe area has been extensively searched for sage~grouse so the actual number of lefcs is cDnsicteted to be mb.c h iiigher.

Impacts to sage-grDuse from CBM development inc1udedirett loss .of

'tats frDm aIIprDduction activities .along with indirect effects from new 'wer lin,es ~d·sig,nifi(:antly higher amOQrit~.of human activlty,rluring both tialdevelopment and during production~ Directhabitat IDSS to sage:-grouse date, with. nearly 12,000· wells in production, inCludes ail· estimated 5,000 es (2,024 hal. CBM activity has affected an estimated 28 percent of the

~Dwn sage~grouse habitats within the projectarea. Development will continue .toMf"ectmDre sage-grouse habitats over the next 30 to 50 years, as new wells are drilled within areas that contain sage-grDuse poPulations and their habitats,

• IdaH oithe project area be placed into prDduction, over 50 percent of the ~ge~grouse range will be either directly or indirectly affected.

11;t}; Sage-grDuse population responses to CBM development are just inning to be observed, as mDSt of the current production has. only ()Ccurred .f the past fDur years and nearly 70 percent of the current production in just . past two years. Although CBM productiori is fairly retent, there are a few ly indications of detrimental affects .onsage-grouse as a result .of this

.• eloPment; There are 200 CBM· wells within 0.25 miles. (0.4 kIn) .of 30 kno\Vn

e-grouse leks. For these leks; there has been significantly fewer males per . and the rate of growth IS much ·lower,compared tD oth~r less disturbed leks

.. . Transactions oj the 6?h North American Wildlife and Natural Resources Conjerencei:J: . 343

(Figure 1). Direct disturhanceand loss of habitats are the suspected these differences.· Some 6,000 niiles (9,656km) of new overhead have been constructed since CBM development began. Another (8,046 kIn) of overhead power lines are exPected as CBM de'llrel(]lpmlenl:co over the next 10 years. Currently, there are 40 known sage-grouse have an overhead power line within 0.25 miles (0.40 km) of the lek, . grouserium:bers for these leks have a significantly lower growth observed on1eks that do nothave an overhead power line so close to the ground. Higher raptor predation rates because of perches are the cause. The proximitY of CBM compressor stations to sage-grouse leks having a meaSurable riegative impaeton sage':grolise.Cirriently, there are 200CBM facilities within 1 inile(1.6km) of asage-grouselek.. . numbers are consistently lower for these leks than they are for leks that have this disturbance. Direct habItat losses from the site itself, roads and and the associated noise are most likely the reasons behirili this· finding, ..

The cumulative impact to sage-grouse from all CBM activiti starting to be observed (Figure 2). Currently, nearly 90 sage-grouse within the CBM development area, orabont 40 percent of the known leks ..

.;c .!l ... 8-'" 0 . . c; ~

20

15

10

5

0 1991 1992 1993 1994 1995 1996 1997 1998 1999

Within area:. Y = 0.3119x2 - 4.8447x + 21.227

Without area. Y = 0.2967x2 - 4.1719x + 20.732

Figure i. Sage-grouse response to CBM wells and drilling in Wyoming. Average males for both leks within \4 mile of a CBM Well (n = 30) and leks outSide \4 mile of a CBM 200). Note, since 1996 when CBM production started to significantly increase, sage response in areas of gas production has been increasing at significantly lower rate that . leks outside of this area.

344 tl Session Five: Oil and Gas Development in Western NorthAmerica. ..

Within area II y = O.3007xl " 3,9538x + 17.495

Without area II Y = O.3209x 1 _ 4.74x+ 23.289

.... ure 2. Sage-grouse response to the cumulative affects of CBM development in Wyoming. are 90 sage grouse ieksthathave CBM development within 2 miles Qfthe lek. Within this

·lifea; there I,Ire 3.688 wells, 168 facilities, and 872 mi~~ ofov:erhead power lines. The amount of Cdirect habitat loss and displacement can only be estimated at this tillie. As development continues, L$iverse affects on sage grousewiU continue. ' ::~. .

I.: northeast Wyoming. As development continues, another 50 to 701ek areas will 'i,~ impacted by CBM. PoplibitiOri monitoring most likely will reveal severe <~nsequencestosage.,grouse from this activity. however thiskIlowledge most t likely wjlI come too late to result in any major initiatives to protect the birds or riiheir habitats. ...... Mitigation of CBM impacts on sage-grouse has been minimal and ,'4sual1y voluntary by the operators involVed becailse nearly 80 percent Of the •. surface ownership is private. On federal lands, companies are required to avoid "'lekdisturbance during the spring breeding. s~son, reduce .compressor noise '. near Ieksand place overhead power lines at least 0,5 mile (0.8 km) from any sage-grouse breeding or nesting grounds. Companies are also required to avoid

(sagebrush habitats when locating' impoundments. All of these requirements can be waived by the federal land management agencies. There are no mitigation . requirements or stipulations for sage~grouse on private land or private mineral

··.·CBM production .

. Concluding Comments

The effects of oil and' gas developments on sage-grouse and other

.'. sagebrush-grassland avifauna are poorly understoodbecau~e of the lack of

Transactions of the 67'h North American Wildlife and Natural Resources Conference ti' 345

replicated, well designed studies .. However, it is cleat tbat all "'''.o::,,",fJ''U

grassland dependent birds have specific habitat requirements,incliiding structure ~d patch size. We believe the immediate effects of Cl. eV~~lOI)ml~n negatIve and are caused by loss ofhl!bitlt and disturbances associated strUcture$. roads and noise-especially during the breeding season. hmtheslzethatthe number 6fbitds of each species willdectease with· deVelopment. then increase. to Saine unknown level below that· development. A return topre:..disturbance levels ofabUlidance is not because .of ioss of habitat .. The lengihof time of the expected rlp,'"",-.",,,,, uUknown and may be species dependent, as well as dependent upon the activity and density of physical disturbances.' Increased roads and power have th~ most potential to be negative, as does the decreasein available Increased long-tenn and well-funded research is needed for all bird "V'-"L~ areas presently and to be developed for oil and gas production, so a scientific basis becomes available. Cause and . effect studies usirtgan

. adaptive management approach (WalterS 1986), are necessary to fully UIJ(leE§:£ the implic~tions ~f energy developments on wildlife species. We believe the responsibility of the oiland gas indus:try to demonstrate that their have no negative impacts initially or eventually. We espeCially: impacts of oil andgas development q.ave been and are negative for ", ... ",7,<.J.V

. and this species, because of itsreqairement for large areas of "'u.o::''-'.LJJL"

doniinated.habitats, it will be placed at risk of local~~tirpation in developed areas; ThU$, Wf; strongly recommend Guidelines to Manage Grouse Populations and th~ir Habitats (Connelly et aI. 2(00) be • all areas with populations Of sage-:-grouse. This is not presently done, as choose which gUidelines to follow and vary. their application among districts and resource areas~ or agencies ina y igl;1ore them; as is the case in Alberta and SaslQttthewan, Finther, it would be desirable to have in application of habitat guidelines for all bird species among all agenc:ies the entire shrub':'steppe region, Finally, tile oil a~d gas,industry should expected to fully mitigate for documented decreases in useable habitat as as in popUlations of specific: bird species, Mitigation should. also those impacts that cari be reasonably expected, including cumulative

. Consideration should be given to the removal Of other uses of sagebruSh that also have cumilhitive· effects on specific avian species as well as wildlife.

346 * Session Five: Oil and Gas Development in Western North America.,_

... Acknowledgments

We thank· M .• D .. Stricklarid arid F. G. Liridzey. for encouraging . the preparation of this paper. And, we thankC: C. Cesar. of the Bilreanof Land

. Management, and J. L. Hicks, of the Colorado Division of Wildlife, who r· ··.provided current data for North Pru;k, Colorado.

~;:

References

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348 -t< Session Five: Oil and Gas Development in Western NoithAmerica ...

t~le. T. R. 1975.Piesettletnent vegetation in the sagebrUsh-grass area of the ~i .. Intermountain West. Jour: Range Manage~ 28:32~36 ... iWalters, C; J. J986. Adaptive management of renewable resources. McGraw ,f;; . Hm, New York, New York 374 pp. ~~iens, J.A. and J. T. Rotenberry. 1981 •. Habitat· associations and community I;;~ structure ofbirdsiil shtubsteppe environmentS. Eeo1. Monogr. 51 :21.: ;~> 41. ~- .....

(:Wiens, J~ A. andJ.T. Rotenberry.19S5; Response ofbreedingp~serine buus ~;~~:.:. to fang~~and altera~OA in a "N9$ American shiu~steppe ~q~al~ty. Jo.ur~ :f,'. .. Applied ECQl. 22:655-668. . ~~ens, I. A.. 1. T.Rotenbenyand B. Van Horne. 1987. Habitat occupancy ~.... patterns of North·American shrubsteppe birds:. The effects of spatial i;' scale. Gikos. 48: 132": 147.

Tran.~actionS of the 67'h North American Wildlife liJid Natural ResourcesCoriference 1::i: 349