My Hummingbird Adventure, by Laurel Rose

This article is reposted with permission from CoyoteYipps, a blog about San Francisco’s urban coyotes. We republish it here as an interesting story – and a lesson in how difficult it is to see a bird’s nest even if you are looking for it. (Emphasis added; all pictures copyright Laurel Rose)

We urge all city departments and homeowners to trim or remove trees only in the safe Fall months: September to December



I learned a valuable lesson this weekend: Do Not Prune or Remove Trees in Spring!

Over the past couple years, I’ve been removing a row of unattractive honeysuckle trees along the fence line to let more light into our shady yard and plant some ferns & other foliage. The trees all had long skinny bare trunks with foliage starting at about 15- 20 feet up so all I could see was fallen leaves on top of compacted dirt and 8 pencil-thin tree trunks.

skinny trees (copyright Laurel Rose)

This weekend 7 and 8 were scheduled for removal. After getting 7 out of the ground, root and all, my friend and & I were getting ready to start breaking the trunk & branches down to 4 foot size segments required by the city for the green waste bins. I had a hand saw and my friend was using my mini electric chain saw for the job. I kept a safe distance in a far corner of the yard and we got to work. 2 branches into it, the chainsaw turns off and I hear “Oh Noooo! Oh my god! Nooo!” then, “chirp, chirp chirp”!

Tiny hummingbird nest on a twig

This is how I found the nest (copyright Laurel Rose)

The tree had a hummingbird nest camouflaged and expertly woven very securely onto a few twig size branches. Both my friend and I love & respect nature so we were a little frantic and horrified at the thought of nearly chainsawing through this little womb-like nest cradling 2 chicks. I found a little box and cushioned it with soft material scraps and toilet paper and placed the nest inside very carefully. It took a good hour for us to calm down and stop focusing on how thoughtless we had been to choose April to remove a tree. Even ugly trees with sparse foliage provide habitat and serve a s food source. My friend, a somewhat burly guy named Terry but whose friends call him “Bubba” was on the verge of tears telling me, “I searched for a nest before sawing off each branch. . .” . Even if one of us has noticed it, it did not resemble a typical storybook nest.
I called every organization and person I could think of for help on that Saturday evening: Golden Gate Audubon Society, Wild Care, and Janet. I was able to listen to a recorded instructions for caring for a injured chick. I kept them inside for the night in a warm dark spot away from my curious little dog who likes to be a part of everything I do whenever possible. As soon as it was light outside, I placed the box up high in the area where the tree had been. Within 20 minutes, mom showed up and fed her hungry babies and I watched as she gathered nectar from the flowers overhead on tree number 8 (which will stay in my yard).

Baby hummingbird (copyright Laurel Rose)

DAY 1: a few hours after discovery

We estimated the age to be between 2 & 3 weeks and were told that hummingbird chicks leave the nest at 23 days old. A couple days before this happens, a stronger chick pushes the weaker out of the nest and it dies because mom will not feed it on the ground. The reason this happens is because the nest is very small and is needed as a “launching pad”. Once the other chick takes flight, mom will continue to feed her baby for several days, teaching how and where to find all the best nectar & bugs before she chases it away to find its own territory. Since they are in a box, neither one will be pushed out of the nest and mom will continue to feed them both. I’m not sure if this may have any negative or unforeseen consequences but I like that idea!

Two hummingbird chicks in the nest

Two hummingbird chicks on the first day

Two Hummingbird chicks

Second Day – Hummingbird chicks

Box put up to rescue hummingbird nest

A safe space for a hummingbird nest

Day 2: I secured a new box in the other Honeysuckle tree because we were having some very windy days.


Box fastened into tree to rescue a hummingbird nest

Box fastened well against the wind

Day 3: I wasn’t sure if Mama was feeding her chicks with the new placement of the box with a different type of access, but I caught her in the act (see video below)


Mama hummingbird entering box to feed chicks in rescued nest

Mama hummingbird entering to feed the chicks – click for video (copyright Laurel Rose)

Hummingbird chick near fledging

Hummingbird chick near fledging

Day 4: They changed so much from one day to the next

Two hummingbird fledglings

Two hummingbird fledglings

Day 5: Just before I left late Thursday morning, I went to check on the chicks and snapped this photo. They looked like they were ready to spread their wings. I might have made them a little nervous putting the camera up so close but wondered if they were contemplating their first flight.

Hummingbird chicks just before departing nest

Hummingbird chicks just before departing nest

When I came home in the early evening, the first thing I did was check the box and it was empty. I stood there for several minutes wondering how such a tiny creature with only 23 days of life can survive on their own. That’s when I heard chirping above and looked up- there was mama with 1 chick shoulder to shoulder on a branch.

hummingbird sitting in chain link fence

Hummingbird sitting in chain link fence

hummingbird-in-wire-2I looked around for the other chick and had noticed what I thought was a leaf caught in one of the links on the fence, but a closer look told me otherwise.

Maybe the little guy didn’t feel quite ready, or maybe he wanted to say goodbye. He let me get real close and looked at me with that one little eye as I said some encouraging words and slowly reached in my back pocket for my camera. I snapped one photo and he flew to the branch up above where his family was.

Today would be Day 8. I’ve been seeing what I believe to be this same little chick hanging out in the honeysuckle tree where the box was. A few hours ago, I observed the mama arrive and feed the chick patiently waiting on a little branch.

If you would like to invite hummingbirds to your yard I would not recommend those feeders with sugar water because they must be cleaned every 3- 4 days or they can make the hummingbirds very sick. It’s much better and healthier to provide their natural food sources and plant things like honeysuckle, sage, fuchsia, Aloe vera and other long tubular flowers that provide both nectar as well as habitat for insects that serve as protein. Hummingbirds also need a place to perch during the day & sleep at night that offers some protection from wind & rain- usually trees. You can also hang a perch up high in a tree near the flowers and you can encourage nesting by providing materials by hanging a “Hummer Helper” you can purchase and fill with store bought material or even dog and cat hair — the “Hummer Helper” is actually just a “suet feeder” which you can buy for a lot less. The best time to start is May. The Hummingbird Society has a lot more tips and information on their website.

*One last note about trimming trees- the safest time is in the Fall during the months of September- December

Woodpecker Diversity in San Francisco

watchful acorn woodpecker (c) Janet Kessler

Watchful acorn woodpecker (c) Janet Kessler

Wildlife photographer Janet Kessler shared these photographs of an acorn woodpecker in Glen Canyon in late August, 2014 (and they’re copyright to her). It was a great capture, though she wasn’t thrilled with the quality. “They were taken under bad lighting at a high ISO,” she explained.

2014-08-27 (1) acorn woodpecker

Acorn woodpecker (c) Janet Kessler

We loved their expressiveness.  Acorn woodpeckers have clown faces with a comical red crown. They reminded us of a childhood song,  ” Hear him pickin’ out a melody/ Peck, peck, peckin’ at the same old tree/ he’s as happy as a bumblebee…”

It’s a delight to find so many species of woodpeckers in San Francisco.

The Audubon Society started its Christmas Bird Counts in 1915, and by 1945 they had held 18 counts. In those 18 counts, only three species of woodpecker showed up: Northern flickers; downy woodpeckers; and acorn woodpeckers like these birds here.

downy woodpecker (c) Janet Kessler

Downy woodpecker (c) Janet Kessler

Northern Flicker(c) Richard Drechsler 2012

Northern Flicker(c) Richard Drechsler 2012


Woodpeckers need trees, preferably mature trees. All those tree-planting efforts from the turn of the last century have created a wonderful habitat for birds. 

Recent Christmas Bird Counts in San Francisco doubled the number of  woodpecker species. In addition to the earlier three,  they showed Hairy woodpeckers; Nuttall’s woodpeckers; and sapsuckers (both red-naped and yellow-bellied, a division that didn’t exist in 1945).

hairy woodpecker (c) janet kessler

Hairy woodpecker (c) Janet Kessler

Hairy woodpeckers, like the ones in the pictures here, are larger than downy woodpeckers and have bigger beaks.

Hairy Woodpecker (c) Richard Drechsler 2009

Hairy Woodpecker in San Francisco (c) Richard Drechsler 2009

This is a red-breasted sapsucker, photographed in San Francisco.

Sapsucker (c) Janet Kessler

Red breasted sapsucker (c) Janet Kessler

And recently, birders have reported seeing a Lewis’s woodpecker in Buena Vista Park, flying between cypress trees and “a tall eucalyptus.”

Lewis's Woodpecker (c) Richard Drechsler

Lewis’s Woodpecker in San Francisco (c) Richard Drechsler


Northern flickers are breeding in the city now. (The photograph here and in the linked article are also by Janet Kessler and copyright to her.) The baby birds in the picture below are nearly grown.

Red-shafted flicker family in eucalyptus tree nest - San Francisco - Janet Kessler

Red-shafted flicker family in eucalyptus tree nest – San Francisco (c) Janet Kessler

Nuttall’s woodpeckers are breeding here too. We’d like to thank Richard Drechsler for these wonderful pictures of a Nuttall’s woodpecker nest, below.

Nuttall's woodpecker in nest (c) Richard Drechsler 2011

Nuttall’s woodpecker in nest (c) Richard Drechsler 2011

It was taken in the Potrero Hill area – where, incidentally, Caltrans is cutting down a lot of trees and neighbors are trying  to save them.

nuttall's woodpecker at nest (c) Richard Drechsler 2011

Nuttalls woodpecker at nest (c) Richard Drechsler 2011

We would like to thank Janet Kessler and Richard Drechsler for giving permission to use their photographs in this article.

Don’t Cut Trees in the Nesting Season!

This year, the issue of tree-trimming or cutting during the nesting season was highlighted by the sad destruction of black-crowned night herons’ nests when the Oakland Post Office decided to get its trees trimmed. Five young herons were injured, others may have died. The tree trimmer potentially faced criminal charges, but was so remorseful – and so willing to pay for the care of the baby herons – that everyone was relieved when he didn’t.

Most people just don’t know that it’s a bad idea to trim trees (or worse, remove them) during the nesting season. Even aggressively trimming undergrowth could damage or destroy birds’ nests.  In San Francisco, the season extends approximately from February to September, depending on many factors including the weather.

Each year, Wildcare, a wonderful organization that rehabilitates hurt or orphaned wildlife,  gets a deluge of baby birds during the summer. Most of  them are displaced by tree-trimming or removal.

2012-04-11 bewick's wren nesting

Birds nests are difficult to spot, even for experts. Herons’ nests are large and noisy, and the Oakland Post Office staff surely knew the birds were there. But most birds hide their nests. Unless they are huge ones like nests of hawks or owls, the parent birds need to conceal their young from predators. Humans, who typically aren’t really looking out for them, would usually miss seeing them altogether. It may take even experienced birders hours of observation to be sure. Nests of hummingbirds, for instance, are around the size of a quarter. They’re common in San Francisco but very difficult to spot.


Here’s Wildcare’s page  “Stop! Don’t Prune Those Trees!”  It explains the problem in a user-friendly way, and also gives references of two bird-friendly arborists who can do emergency work if needed.

 “Spring (and summer!) are busy baby season— procrastinate now!

When is wildlife nesting? There is some variation, but most wild animals have their babies in the spring, between March and June. However, many species will also have a second brood in July or August if food supplies are sufficient. If you can plan to trim your trees in the winter months, you can completely avoid the possibility of damaging a nest. It’s also a healthier time for the trees, when the sap has gone down and trees will be in their dormant phase. Call WildCare at 415-456-7283 if you’re unsure when it is a safe time to trim or remove a tree. “

The Golden Gate Audubon Society has published an excellent brochure:  Healthy Trees, Healthy Birds that is available as a PDF on their website. Here are pictures of the brochure (the download will be clearer and can be printed).

GGAS Healthy Trees Healthy Birds brochure 1

GGAS Healthy Trees Healthy Birds brochure 2


Disturbing – or worse, destroying – a birds nest is illegal. It’s a strict liability offense punishable by up to six months in jail and/or a $1,000 fine per offense.  There are laws at the Federal, State and City level. Here’s what they say:

  • Federal Migratory Bird Treaty Act. This applies to over 1,000 bird species, including many that are found in San Francisco. It makes it ” …illegal for anyone to take, possess, import, export, transport, sell, purchase, barter, or offer for sale, purchase, or barter, any migratory bird, or the parts, nests, or eggs of such a bird…” (“Taking” means to harass, harm, or pursue a bird.)
  •  California State Code 3503, 3503.5: ” It is unlawful to take, possess, or needlessly destroy the nest or eggs of any bird, except as otherwise provided by this code or any regulation made pursuant thereto.”  California State Code 3503.5 relates to birds of prey: ” It is unlawful to take, possess, or destroy any birds in the orders Falconiformes or Strigiformes (birds-of-prey) or to take, possess, or destroy the nest or eggs of any such bird except as otherwise provided by this code or any regulation adopted pursuant thereto.”
  • San Francisco County Municipal Code 5.08: It’s unlawful “to hunt, chase, shoot, trap, discharge or throw missiles at, harass, disturb, taunt, endanger, capture, injure, or destroy any animal in any park...” (with exceptions for small rodents like gophers).

The general rule is to stay 50 feet away from song-bird nests, and 500 feet from raptor nests.


Sometimes, trees are removed because they’re in poor condition – dead or dying. Those are often the very trees that birds love, especially those that nest in cavities. Like this flicker (a kind of woodpecker) nesting in a half-dead eucalyptus tree. If you weren’t watching very patiently, you would have no idea that a family of young birds (three in this case) were being raised here.

The eucalyptus-tree nest hole of the red-shafted flicker - San Francisco. Janet KesslerPLAYING SAFE

The only safe way is to NEVER cut trees or thin dense bushes during the nesting season – and even when working in the off-season, typically September to February, to be very observant and watchful before starting work.

Young Great Horned Owls being raised in Eucalyptus tree

Eucalyptus Tree Hosts a Flicker Family

Note: All these photographs are by wild-life photographer Janet Kessler.

In San Francisco’s Presidio, there’s an old, rather dilapidated eucalyptus tree. The main trunk is broken off  and ragged shafts stick in the air. Though it’s still alive, you might say that it’s ‘in decline.’

Just another eucalyptus tree 'in decline' - Janet Kessler

But this eucalyptus tree holds new life. A red-shafted flicker – a kind of woodpecker – has excavated a nest-hole.

The eucalyptus-tree nest hole of the red-shafted flicker - San Francisco. Janet Kessler

In it, there are three or four chicks.

Red-shafted flicker family in eucalyptus tree nest - San Francisco - Janet Kessler

Ever wondered how woodpeckers get insects out of their holes? Look at this tongue!

red-shafted flicker sticks out its tongue - Janet Kessler

They’re growing big, and soon they’ll move along.

Red-shafted flicker parent and chick on a eucalyptus tree - San Francisco - Janet Kessler

Then this hollow in the tree may host another family – bluebirds, maybe, or owls or swallows or chickadees or even bees.  It’s a feature of the ecosystem – and a strong argument for leaving in place trees that aren’t actually hazardous, even if they are apparently in decline or even dead. Even if they’re non-native eucalyptus, sheltering native flickers.

Birds, Bees, and “Natural Areas”

One of the concerns we have with the way our wild lands are being managed is the disrespect for habitat. Many of those who support these actions – felling ‘non-native’ eucalyptus trees, removal of trees that are dead or dying even if  they’re not hazardous, stripping away ivy and understory vegetation – don’t actually realize the impacts on the wildlife that call those habitats home. (All the photographs here are courtesy wildlife photographer Janet Kessler.)


Eucalyptus trees are hugely important as habitat trees. They provide cover and nest sites for birds as large as Great Blue Herons and Double-Crested Cormorants and hawks and Great Horned Owls – and as small as Pygmy Nuthatches.

[Edited to Add: For more pictures of heron and cormorant nests – and the story that goes with them – please see the latest article on the Coyote Yipps blog. ]

2013-05-14 great blue herons nest

Great Blue Heron Nests in Eucalyptus – Photo: Janet Kessler

2013-05-142  double-crested cormorants nest

Double-crested cormorants nest – Photo: Janet Kessler

2013-05-13 eucalyptus rookery herons cormorants

Rookery tree – Photo: Janet Kessler

Young Great Horned Owls being raised in Eucalyptus tree

Young Great Horned Owls being raised in Eucalyptus tree. Photo: Janet Kessler

Their branches and trunks provide a hunting ground for small birds like kinglets and Brown Creepers.

Brown creeper forages on eucalyptus

Brown creeper forages on eucalyptus. Photo: Janet Kessler

Since they flower in winter when few other food sources are available, they provide nectar for insects – and the birds that feed on the nectar, the insects, or both. Honeybees in particular depend on winter-flowering eucalyptus. Cavities provide nesting spot for some birds – and even bees, like Glen Canyon’s last remaining bee hive tree.

bees in euc

Beehive in eucalyptus tree (bees circled in red) – Photo: Janet Kessler


Dead or dying trees – of every species – are valuable habitat, for two reasons. They’re more likely to have cavities that are suitable for nesting (and are easier to excavate for woodpeckers and other cavity-building species). They also have bugs that come to feast on the decaying wood, and that’s bird-food.

2013-05-21 (2) hairy woodpecker

Hairy woodpecker in Glen Canyon Park. Photo: Janet Kessler

Unfortunately, the San Francisco Recreation and Parks Department – and now UCSF in its management of Sutro Forest – looks to remove ‘snags’ and dying trees.  They’ve been removed in Glen Canyon Park, and in Golden Gate Park, and this fall, massive removals could start in Sutro Forest.

2013-05-21 hairy woodpecker

Glen Canyon Park, Hairy Woodpecker. Photo: Janet Kessler

If that happens, it will have a negative impact on all the woodpeckers and cavity-nesting species of birds and even bats. It’s extremely important to leave these ‘in-decline’ trees as habitat, unless they are actually hazards.


Smaller birds and animals in particular need the cover provided by ivy and understory plants to hide from predators – and to nest.

Here’s a picture of a tiny Bewick’s Wren outside its Glen Canyon nest, taken in 2012. The tree it’s nesting in is so ivy-covered you can’t actually see it. The nest is completely hidden.

2012-04-11 bewick's wren nesting

Bewick’s wren outside nest. Photo: Janet Kessler

Here’s the same tree this year. The ivy is gone, the understory mowed down. Is the wren coming back? Not too likely.

2013-05-19 no nesting spot for wren

This year there’s no nesting spot for the wren. Photo: Janet Kessler

Natural Areas Plan: SFFA comments on the DEIR (Pt 3: Wildlife)

Bewick’s wren at nest site

One of the reasons we oppose the Natural Areas Program is that it’s harmful to the birds and animals of this city. They destroy habitat — the trees and thickets that serve as cover and breeding grounds, exposing song-birds to predators; they do not respect the breeding season even though they claim to do so; and they use pesticides that can harm wildlife, whether insects, amphibians or other creatures.

Read on for the details.

In this public comment, we will provide evidence that the Natural Areas Program has had a significant negative impact on legally protected wildlife as well as all wildlife in San Francisco’s parks.

  1. The Natural Areas Program has violated California Fish & Game Code, Sections 1600-1616 regarding streambed alteration and the federal Migratory Bird Treaty Act by conducting the destructive phase of their project in Glen Canyon Park during breeding and nesting season.
  2. The Natural Areas Program is violating the Endangered Species Act by using pesticides known to be harmful to butterflies on Twin Peaks, where they have been reintroducing the endangered Mission Blue butterfly for several years.
  3. The Natural Areas Program harms all of the animals in the parks by poisoning and eradicating the thickets in which they den and nest and the food which they eat.


The Draft Environmental Impact Report (DEIR) states that SNRAMP is consistent with all federal and state laws governing the protection of biological resources.  One of those laws is California Fish & Game Code 1600-1616 regarding the protection of fish and wildlife within “bodies of water of any natural river, stream or lake.”  These codes obligate those who are engaged in any “streambed alteration” to apply for a permit and “to propose reasonable project changes to protect the resource.”  (DEIR, page 274)

Islais Creek in Glen Canyon Park is such a water body which is protected by this law.  Accordingly, the Natural Areas Program applied to California Fish & Game for a Streambed Alteration Permit in preparation for their project which began in November 2011.  The Natural Areas Program made the following commitment to mitigate harm to wildlife in Glen Canyon Park in its Streambed Alteration Permit:

“It is the policy of RPD’s Natural Areas Program that no new projects will begin during the breeding season (December to May).  Follow up work in previously cleared areas may be done during the breeding season, however, because areas will have been cleared previously. Wildlife will not likely be using these areas for breeding.  This protocol has been effective in reducing impacts to breeding wildlife.”

The Natural Areas Program began to destroy the non-native vegetation in Glen Canyon Park in San Francisco in November 2011.  In addition to destroying valuable habitat with chainsaws, they also sprayed herbicides.  This destructive activity continued through winter and spring 2012 and cannot be dismissed as “follow-up work” on previously cleared areas.  The San Francisco Forest Alliance (SFFA) protested this destructive project many times but it has continued unabated to as recently April 27, 2012, when they pruned trees and sprayed herbicides.

Earlier in April, SFFA learned from a public records request that this project violated a legal commitment to the California Department of Fish & Game.  SFFA immediately brought this violation of NAP’s commitment to the attention of the General Manager of the Recreation and Park Department.  The head of the Natural Areas Program said that the violation was necessary because the grant funding for the project was about to expire.  To avoid losing the funding for the project, the birds and animals of Glen Canyon Park were subjected to this destructive project during their breeding and nesting season.

SFFA brought this violation to the attention of the California Department of Fish & Game.  Their regulations commit them to enforce the terms of the Streambed Alteration Permit, including the mitigation of potential harm to wildlife.  Violations of the terms of the permit are subject to “civil penalties” according to the regulations:  “A person who violates this chapter is subject to a civil penalty of not more than twenty-five thousand dollars ($25,000) for each violation.”

One month after informing California Department of Fish & Game of this violation, nothing seems to be done about it.  In fact, several weeks after sending this information to Fish & Game, another episode of destruction occurred in Glen Canyon Park on April 27, 2012.

As the breeding/nesting season is also the season during which migratory birds are occupying their nests and the federal Migratory Bird Treaty Act “…also applies to the removal of nests occupied by migratory birds during the breeding season,” (DEIR, page 273) we assume this law was also violated.

In other words, the legal commitments made by the Natural Areas Program to conduct the destructive phase of their project outside of the breeding and nesting season were not observed.  Furthermore, no action was taken by California Fish & Game to stop this project when it was brought to their attention.  The law is apparently ignored with impunity.

In addition to the violation of federal and state laws, the Natural Areas Program has also violated the commitments made in both the SNRAMP and the DEIR:  “In compliance with the MBTA [Migratory Bird Treaty Act], the SFRPD would avoid harming or removing the nests of these species and any migratory bird species.  Measure GR-4b (page 109) in the SNRAMP requires that vegetation management activities be conducted outside the breeding season (February 1 to August 31), unless these activities had already begun before the breeding season and had already removed nesting habitat or if a breeding bird survey was conducted prior to vegetation removal activities and had determined that no nesting birds were present.” (DEIR, page 305)

The commitment to California Fish & Game in NAP’s Streambed Alteration Permit and the commitment made in Measure GR-4B of SNRAMP are contradictory.  These contradictions should be resolved by the final EIR:  When is the breeding season?  What evidence is there that a breeding bird survey was conducted prior to vegetation removal activities which took place continuously from November 2011 to April 27, 2012?  Is the mitigation required by the Streambed Alteration Permit consistent with the caveats of Measure GR-4b?


The Mission Blue butterfly is a federal endangered species which existed historically on Twin Peaks in San Francisco.  San Francisco’s Natural Areas Program has been trying to reintroduce the Mission Blue to Twin Peaks for several years, so far with limited success.  This reintroduction effort is reported by the DEIR. (DEIR, page 285)

Herbicides are being sprayed on Twin Peaks to control non-native vegetation.  Twin Peaks was sprayed with herbicides 16 times in 2010 and 19 times in 2011.

A recently published study reports  that the reproductive success of the Behr’s metalmark butterfly was significantly reduced (24-36%) by herbicides used to control non-native vegetation.  Two of those pesticides are used on Twin Peaks, imazapyr and triclopyr.  Triclopyr was used most often on Twin Peaks in 2010 and imazapyr in 2011.

The study does not explain how this harm occurs.  It observes that the three herbicides that were studied work in different ways.  It therefore speculates that the harm to the butterfly larva may be from the inactive ingredients of the pesticides which they have in common, or that the harm comes to the larva from its host plant which is altered in some way by the herbicide application.  Either theory is potentially applicable to the herbicides used on Twin Peaks and consequently harmful to the endangered Mission Blue.

The Endangered Species Act requires that the Natural Areas Program stop spraying these herbicides on Twin Peaks because they are known to be harmful to the reproductive success of butterflies.  Unless further scientific study exonerates these herbicides, the law obligates us to prohibit their use where the endangered Mission Blue butterfly is known to exist, i.e., on Twin Peaks.


The DEIR states repeatedly throughout the document that habitat will be improved by the eradication of non-native plants and the presumed replacement by native plants.  In fact this is offered as the basis for most claims in the DEIR that the “restoration” project will not harm the environment.  For example, although the DEIR acknowledges that the environment may be harmed by the methods used to eradicate non-native plants, this harm is theoretically mitigated by the claim that the eventual development of native habitat will compensate for that harm.  These claims are not supported by either the reality of restoration efforts in the past 15 years or by scientific evidence which does not substantiate a claim that native vegetation provides habitat for animals that is superior to non-native vegetation.

Although non-native vegetation has been removed repeatedly in many natural areas, the native plants that are planted in their place rarely persist for longer than a few months.  These newly planted areas are quickly over run by non-native weeds.  We will provide examples of such failed “restorations” in a subsequent section of this comment (Part V).

More importantly, neither SNRAMP nor the DEIR provide any scientific evidence to support the contention that native vegetation provides superior habitat to animals.  In fact, all available scientific evidence contradicts this claim.

Because eucalyptus trees are one of the primary targets for eradication, we will focus on the specific claim that the eucalyptus forest is a “biological desert.”   We are frequently told that “nothing grows” under the eucalypts and that they are not providing food or habitat to insects, birds, and other animals.

Professor Dov Sax (Brown University) tested these claims while a student at UC Berkeley.  He studied the eucalyptus forest in Berkeley, California, and compared it to native oak-bay woodland in the same location.  He found little difference in the species frequency and diversity in these two types of forest.

He studied six forests of about 1 hectare each, three of eucalypts and three of native oaks and bays in Berkeley, California.  The sites were not contiguous, but were selected so that they were of similar elevation, slope, slope orientation, and type of adjacent vegetation.  He conducted inventories of species in spring and autumn.  He counted the number of:

  • Species of plants in the understory
  • Species of invertebrates (insects) in samples of equal size and depth of the leaf litter
  • Species of amphibians
  • Species of birds
  • Species of rodents

He reported his findings in Global Ecology and Biogeography :

“Species richness was nearly identical for understory plants, leaf-litter invertebrates, amphibians and birds; only rodents had significantly fewer species in eucalypt sites.  Species diversity patterns…were qualitatively identical to those for species richness, except for leaf-litter invertebrates, which were significantly more diverse in eucalypt sites during the spring.”

Professor Sax also surveyed the literature comparing biodiversity in native vs non-native forest in his article.  He reports similar findings for comparisons between non-native forests and local native forests all over the world:

  • In Spain, species of invertebrates found in the leaf-litter of eucalyptus plantations were found to be similar to those found in native forests, while species richness of understory plants was found to be greater in the native forests.
  • In Ethiopia the richness of understory species was found to be as great in eucalyptus plantations as in the native forest.
  • In the Mexican state of Michoacán, species richness and abundance of birds were found to be similar in eucalyptus and native forests.
  • In Australia species richness of mammals and of soil microarthropods were found to be similar in native forests and in non-native forests of pine.

The only caveat to these general findings is that fewer species were found in new plantations of non-natives less than 5 years old.  This helps to illustrate a general principle that is often ignored by native plant advocates.  That is, that nature and its inhabitants are capable of changing and adapting to changed conditions.  In the case of non-native forests in the San Francisco Bay Area, they have existed here for over 100 years.  The plants and animals in our forests have “learned” to live in them long ago.

The scientific literature informs us that wildlife does not necessarily benefit from native plant restorations and sometimes they are harmed by them.  The assumption that native animals are dependent upon native plants underestimates the ability of animals to adapt to changing conditions.

Art Shapiro (UC Davis) has been studying California butterflies for over 35 years.  His own observations as well as the work of other scientists have informed him that “…the extensive adoption of introduced host plants has clearly been beneficial for a significant segment of the California butterfly fauna, including most of the familiar species of urban, suburban and agricultural environments.  Some of these species are now almost completely dependent on exotics and would disappear were weed control more effective than it currently is.”

He explains that this is particularly true on the coast of California because this is where the highest concentration of introduced species of plants is naturalized and the butterfly population is less diverse because of the cool, foggy climate.  There are apparently few non-native plants in the desert and alpine regions of California and so butterflies in those regions have not had the opportunity or need to adapt to new plants.

Professor Shapiro also speculates in this study that other insects have adapted to non-native plants as well:  “Introduced hosts, having a broader geographic range than native hosts, may permit the expansion of the insect population geographically.”

Birds have also adapted to non-native plants and trees.  Researchers at UC Davis surveyed over 1,000 ornithologists in 4 states, including California, about their observations of native birds and non-native plants.  Responses from 173 ornithologists reported 1,143 “interactions” of birds with introduced plants considered invasive.  Forty-seven percent (47%) of those interactions were birds eating the fruit or seeds of non-native plants and trees considered invasive.  Other interactions were nesting, perching, gleaning [eating insects], etc.

Interactions were frequently reported in non-native blackberry, which is found in most parks in San Francisco.  It is one of the most productive food sources for birds in San Francisco.  Unfortunately, it is being eradicated by the Natural Areas Program along with a long list of non-native shrubs which provide food and cover, such as cotoneaster, fennel, etc.  The loss of food and cover has a drastically negative impact on the animals that live in our parks.

The non-native blackberry also provides cover for wildlife.  It is an impenetrable bramble both physically and visually.  Birds and small mammals hide and make nests and dens in these thickets.  Coyotes are resident in San Francisco.  The thick undergrowth which has been removed in some parks by the Natural Areas Program now allows unleashed dogs to pursue them in areas where they were protected before.  If the safe havens of urban wildlife are destroyed, the animals may seek shelter elsewhere, a move that may be dangerous for them.  When animals move into residential neighborhoods they are considered a nuisance and are often killed.

Native plant restorations also require the use of herbicides to eradicate non-native trees and plants.   Herbicides are being sprayed in the blackberries and other berry-producing non-native plants which are a major food source for wildlife.  One study performed by the US Forest Service for the EPA reported that the use of Garlon significantly reduced the reproductive success of birds.    Garlon is also highly toxic to aquatic life.

Finally, we provide a current and local example of the scientific evidence that native plants do not provide habitat that is superior to that provided by non-native plants.  The California Academy of Sciences finds that several years after planting its roof with native plants, it is now dominated by non-native species of plants in the two quadrants that are not being weeded, replanted and reseeded with natives.  Their monitoring project recently reported that there were an equal number of insect species found in the quadrants dominated by native plants and those dominated by non-native plants.  Where equal numbers of insects are found, we can expect to find equal numbers of birds and other animals for which insects are food.


  • The final EIR is not in a position to reassure the public that the implementation of SNRAMP will not harm wildlife because the Natural Areas Program has violated the laws that theoretically protect wildlife.
  • The final EIR must prohibit the use of pesticides known to be harmful to butterflies on Twin Peaks where the endangered Mission Blue butterfly has been reintroduced by the Natural Areas Program.
  • The final EIR must provide scientific evidence that native plants provide superior habitat for wildlife.  If it is unable to provide such evidence, these claims must be removed from the final EIR.  Without such reassurances, the final EIR must conclude that the eradication of non-native plants will have a significant negative impact on the biological resources in San Francisco’s natural areas.

It’s Still the Breeding Season!

San Francisco’s Recreation and Parks Department (SFRPD) thinks the breeding season for birds is December to May. That’s according to an application the SF Rec and Park Department made to California Fish and Game (in the context of a streambed alteration permit for Islais Creek in Glen Canyon).

Someone forgot to tell the birds. Here it is, June 9th, and the American Robin below – raising its family in Glen Canyon – clearly hasn’t got its chicks out of the nest yet. Maybe it’s the economy…

More seriously: We urge SFRPD to recognize that the San Francisco breeding season lasts throughout the summer, and respect that. The Significant Natural Reasource Areas Management Plan (SNRAMP, “Sin-Ramp”) seems to recognize that  it’s only in August that they’ll be done: It quotes February 1- Aug 31 as the  breeding season.

Until then, working in wildlife areas – which includes most of the wilder areas of our parks – is likely to destroy wildlife families.


We just read a heart-warming story from WildRescue about re-nesting two red-shouldered hawk chicks on June 5. It happened in Atherton, an hour down the peninsula from San Francisco.  Two hawk babies survived a fall from their nest, and the rescuers were able to successfully re-nest the youngsters in the same tree, checking to make sure the parents were still in the area.

(To read the whole story, CLICK HERE.)

What was not so heart-warming was how it happened: a huge eucalyptus tree was being trimmed, and the tree-trimmers accidentally cut off the branch supporting the nest. The company responsibly took the chicks to the Peninsula Humane Society, who called Wildlife Rescue; and later worked with Wildlife Rescue to place the baby hawks back in the tree.

But it didn’t have to happen. What it underlines is this:


Had those been songbirds rather than hawks, would they have even survived?]