beavers role in creating and maintaining haitat in ... · srf conference, davis ca march 29 ......

Natural Resources Services- Redwood Community Action Agency

BEAVERS ROLE IN CREATING AND MAINTAINING HABITAT IN CALIFORNIA’S ESTUARIES

Elijah Portugal Redwood Community Action Agency

Contributions: Joe Wheaton, Wally Macfarlane; Utah State University

Redwood Symposium Sept. 15th, 2016


Elijah Portugal - Introduction

Projects Coordinator/Geomorphology/Hydrology- RCAAEducation

• 2014 MS. Geomorphology/Hydrology, Utah State University, Logan UT.

• 2008 BS. Fisheries Biology, Humboldt State University, Arcata, CA.

Background• Fish Habitat

• Watershed-scale erosion and sediment dynamics

• Beaver as ecosystem engineers, ‘partnering’ in a restoration context while mitigating for nuisance behavior


Workshops On Beaver Restoration

Website: http://beaver.joewheaton.org/

Tons of other resources on the website:

Beaver Restoration Guidebook published by USFWS:

http://www.fws.gov/oregonfwo/ToolsForLandowners/RiverScience/Documents/BRG%20v.1.0%20final%20reduced.pdf

State of Beaver Restoration in California Workshop

SRF Conference, Davis CA March 29 –April 1, 2017

http://beaver.joewheaton.org/


Partnering with Beaver…in Estuary Restoration?

I. Introduction, overview and objectives

II. Estuaries, degradation and beaver extirpation

III. Beaver ecology & dam building basics

IV. Management, conservation & restoration planningI. Beaver Restoration Assessment Tool and Beaver Dam Analogs

V. Questions/Comments?


How Does This Relate to Redwood Science?

ESTUARY BASICS

• Coastal, forested northern CA watersheds terminate in estuaries

• Dynamic depositional setting, complex network of salt, brackish and freshwater channels supporting a range of stream velocities and habitat types

• High Sediment supply and hydrology -> High rates of lateral migration, overbank flow and channel avulsion

• Wet (high water table), low gradient, wide valley bottoms: spruce, alder, willow dominant trees with salt tolerant shrubs, forbes and grasses also present. Redwoods on hillslopes


ESTUARY BASICS

• Buffer between ocean and river (combat climate change)

• Benefit flood control, water quality

• Highly biologically productive, support highly variable aquatic, wetland and riparian habitat for endangered salmonids and other species

• SONCC Coho Recovery and numerous other studies identify loss of estuarine habitat and beaver trapping as factors leading to ESA listing (NMFS 1997)

• Geomorphic and ecological setting = Excellent beaver habitat!


Estuary Degradation

Nationally - 2/3 of estuarine wetlands lost over last century / California - 91% of wetland habitat lost

Figures: SFEI San Francisco Estuary Institute & Aquatic Science Center


Estuary Degradation

Diked, drained and leveed for ag., grazing and urban dev

Complex multithreaded planform, high water table, highly heterogeneous habitat

Simplified, single thread planform, water table drops , homogeneous habitat

Widespread estuary degradation took place in northern CA after beaver were largely extirpated and has coincided with decline of pacific salmonids in northern CA


Beaver are Native to Coastal Northern California

• Lanman et al., 2013; Lundquist et al., 2013

– Evidence of historic beaver occupation:

– Mattole R. Estuary

– Klamath R. Estuary

– Humboldt Bay Tribs

– Mendocino Coast

– Other locations inland


Beaver Nearly Extirpated from Coastal CA by early 1900’s

– Inaccurate range in CA originally est. in 1937 (Grinnell) and 1942 (Tappe) after beaver had been nearly extirpated

– Estuary beaver particularly vulnerable to maritime fur trade and Spanish missions late 1700’s and early 1800’s


California Beaver on the Rebound

– Increasing evidence of past occupation and reestablishment in historic range

– Trapping pressure reduced, natural predation down


Beaver as a Restoration Agent in California

I am going to talk a bit about beaver, restoration strategies using beaver and techniques to deal with nuisance behavior

• To do this, we need to: Know a bit about beaver biology/ecology

– Focus on their role as ecosystem engineers (dam building)

– Understand where in the landscape such strategies makes sense

From: www.ankn.uaf.eduFrom: http://wolfmaan.ca/wp-content/uploads/2011/10/beaver_lodges.jpg


The Hope is…

• Beaver can

– Help us restore degraded streams, rivers and estuaries for a lot less $ than traditional methods and create a restoration model that increases local employment opportunities

– Promote dynamic behavior in streams & rivers that leads to better water quality, healthier ecosystems & higher biodiversity


But Lets Not Forget They Can Be Pests!

• In residential areas they can cause flooding…

• They often block culverts, which can flood roads

• They can chop down our ornamental landscape trees

• They can make a mess of irrigation diversions


II. Beaver Ecology And Dam Building

I. Bit of Beaver Biology

II. Why do Beaver Build Dams?

III. Beaver Ecology -> Eco-geo-hydro feedbacks

Bridge Creek © Wheaton From: http://www.howstuffworks.com/beaver-dam.htm

http://www.howstuffworks.com/beaver-dam.htm


A Habitat Generalist And Highly Adaptable • Lakes• Rivers and streams• Abandoned channels on

floodplains• Freshwater and Brackish

Wetlands

Pierre Côtacute

California Academy of Sciences

Slide from John Stella


A Habitat Generalist And Highly Adaptable

Hood et al., 2012 – Skagit Bay Delta Estuary

Hood, W.G., 2012. Beaver in Tidal Marshes: Dam Effects on Low-Tide Channel Pools and Fish Use of Estuarine Habitat. Wetlands, 32(3): 401-410.


Common Habitat Ingredients: Water + Trees

• Northern tundra and treeline range boundary: wood limitation

• Southern desert range boundary: perennial streamflow and/or wood limitation

• Updated distribution to include coastal CA and OR: See Lanmanet al, 2013

Wood limitation

Waterand/or wood

limitation

Slide from John Stella


What Do Beaver Eat?

• Spring/Summer: herbaceous plants, incl. aquatic and riparian forbs, grasses, grains and row crops

• Fall/Winter: tubers, bark and cambium of cached woody plants

• Woody plants comprise ~85% of winter diet; ~15% of summer diet

Photo: C. Demers, SUNY-ESF


A Beaver Food Cache……..


‘Central Place’ Foragers

• Forage from lodge

• Preferences depend on what is available (aspen, willow, cottonwood, alder)

• 100m or less from water

Nicola Plowes, ASU

Lodge

Lodge


II. Beaver Ecology & Dam Building

I. Bit of Beaver Biology

II. Why do Beaver Build Dams?

III. Beaver Ecology -> Eco-geo-hydro feedbacks




So Why Do They Build Dams?


Aquatic Habitat Is Critical For Their Success

• Beaver more agile in water than on land; maximize time in the water

• Ponds provide cover from predators and foraging pathways

• Lodge includes underwater entrance, nest area above water

Photo by Anna M. Harrison

From: https://c2.staticflickr.com/6/5480/14429320108_de16bb8a94_b.jpg

https://c2.staticflickr.com/


II. Beaver Ecology & Dam Building

I. Welcome & Objectives

II. Bit of Beaver Biology

III. Why do Beaver Build Dams?

IV. Beaver Ecology -> Important feedbacks




Beaver Dams Trap Sediment -> Expand Riparian and Wetlands

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Pollock et al. 2007


Beaver Dams can Change Hydrology


Beaver Impacts on Fish?

Kemp et al. 2012


Beaver Dams Benefit Endangered Salmonids

Bouwes et al., 2016 – Population level, watershed-scale increase in density, survival and production of juv. steelheaddue to natural and artificial beaver dams

NO IMPACT TO FISH MOVEMENT>35k steelhead tagged over 8 years with 4 stat ant. and yearly mobile surveys

Bouwes, N. et al. Ecosystem experiment reveals benefits of natural and simulated beaver dams to a threatened population of steelhead (Oncorhynchus mykiss). Sci. Rep. 6, 28581; doi: 10.1038/srep28581 (2016).


Beaver Benefit Endangered Salmonids in Estuaries

LOTS of studies showing beaver ponds benefit salmonids in estuaries: (Rutherford 1964; Bustard and Narver 1975; Swales et al., 1986, 1988; Murphy et al., 1989; Keast and Fox, 1990; Baker and Hill, 2003; Pollock et al., 2004; Cooper, 2007; Hood 2012)

Habitat Benefits:

-Flow Refugia (Pollock et al., 2004)

-Increased Foraging Opportunities (Keast and Fox, 1990)

-Increased Size and Productivity (Bustard and Narver 1975;

Swales et al., 1986, Wallace, 2007, 2009)

-More Cover (Keast and Fox, 1990)

-Higher Over Winter Survival Bustard and Narver 1975; Swales et

al., 1986)

-Prevent Seasonal Floodplain Drying (Cooper, 2007)

From: Bouwes et al., 2016


Management Conservation & Restoration Planning

I. Let’s not forget, they can be pests!

II. Living with Beaver?

III. Restoration by Rodents?

IV. Where? Meet the BRAT

V. Take Homes…


Traditional Removal Methods Don’t Work for Long

• Dynamite and lethal removal largely: expensive, ineffective and lose benefits of beaver

• Boyles and Savitzky, 2008 -> Living with Beaver strategies less-expensive, more effective retain beaver benefits


‘Living’ With Beaver Strategies…

• Is problem real or perceived?

• If real:

– ‘Beaver Deceivers’

– ‘Pond Levelers’

– ‘Caging’ trees

– All require $$ and maintenance

If those don’t work, live trap and relocation


Some Guidelines For ‘Living’ With Beaver

Beaver Restoration Guidebook: http://www.fws.gov/oregonfwo/ToolsForLandowners/RiverScience/Documents/BRG%20v.1.0%20final%20reduced.pdf

Tippie, 2010

http://www.fws.gov/oregonfwo/ToolsForLandowners/RiverScience/Documents/BRG v.1.0 final reduced.pdf


Beaver Management Plans

• Balance the needs of landowners and the public with the benefits that beaver provide

• Common sense solutions to beaver nuisance behavior


MANAGEMENT, CONSERVATION & RESTORATION

I. Let’s not forget, they are pests!




V. Other Planning Tools

VI. Take Homes…


Letting Beaver Do Restoration Is Not New• As early as 1930s, beaver used as

conservation tool

• In CA beaver relocated for erosion control 1923-1950 in 58 counties*

• Logic is simple… just take nuisance beaver and relocate them where we want their ecosystem engineering expertise

* “It is now understood that soil erosion and shortage of water in some places resulted from the destruction of the beavers which formerly built, and kept in repair, dams on the upper reaches of many streams.” – Donald Tappe CDFG 1942


Popularity Growing Rapidly in CA

• Martinezbeavers.org - Heidi Perryman

• Occidental Arts and Ecology Center’s Water Ins. - Kate Lundquist and Brock Dolman

• Scott River Watershed Council –Betsy Stapleton, Charnna Gilmore

• Riverbend Sciences – Eli Asarian• Yurok Tribe• Rocco Fiori• Mid Klamath Watershed Council –

Will Harling• Sanctuary Forest• And others


Yurok Tribe: Tributary to Klamath River Estuary


At Least 6 Types of ‘Beaver’ Restoration

1. ‘Allow’ beaver to stay & promote/protect them (i.e. living with beaver)

2. Accidental beaver restoration

3. Transplant beaver from one area to an area where they are not currently & let them have at it

4. Riparian restoration & land use changes followed by transplanting beaver

5. In areas where beaver alone are not enough, help out with beaver dam analogues (BDAs), then hope beaver take over maintenance

6. Mimic beaver dam impacts with BDAs and artificially maintain…

Passive

Active


A quick Interlude: What the heck are BDAs? Beaver Dam Analogs (BDAs)

I thought Beaver were supposed

to do the work???


Beaver Dam Analogs (BDAs) -Complexes

Mimic the form and function of beaver dams, function together to achieve restoration objectives


MANAGEMENT, CONSERVATION & RESTORATION

I. Let’s not forget, they are pests!




V. Take Homes….


BRAT: Beaver Dam Capacity Model

• Resolves where and at what level (within a drainage network) beaver dams can be built and sustained.

What’s the maximum # of dams this reach can support?


http://brat.joewheaton.org

Two main components:1. Beaver dam capacity model2. Decision support and planning tools

http://brat.joewheaton.org/


Take Homes: Opportunities for Beaver-Assisted Estuary Restoration

• Beaver are native to California’s estuaries

• Beaver are keystone species, profoundly influence the type and distribution of aquatic, wetland and riparian habitat

• Beaver create off-channel habitat critical to the recovery of coho and other salmonids

• We can mimic natural beaver dams with BDAs

• Natural and artificial beaver dams don’t make sense everywhere use BRAT and other tools to prioritize beaver-assisted restoration


Acknowledgements

• Joe Wheaton (USU/ETAL)

• Wally Macfarlane (USU/ETAL)

• Nick Bouwes (ELR/USU)

• John Shivik (USFS/UDWR)

• Kent Sorenson (UDWR)

• Dan Keller (UDWR)

• Michael Pollock (NOAA)

• Mary O’Brien (GCT)

• Jordan Gilbert (USU/ETAL)

• Chris Jordan (NOAA)

• Carol Volk (SFR)

• Nick Weber (ELR)

• Nate Hough-Snee (USU/ETAL)

• Martha Jensen (USU/ETAL)

• Kenny DeMeurichy (USU/ETAL)

• Ryan Lokteff (USU/ETAL)

• CHaMP Field Crews

• Tim Beechie (NOAA)

• And many others…

Countless field crews & collaborators


Questions/Comments??

Let us do what we do best to

restore endangered

species!